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[binutils-gdb.git] / binutils / doc / binutils.texi
1 \input texinfo @c -*- Texinfo -*-
2 @setfilename binutils.info
3 @c Copyright 2001, 2002, 2003 Free Software Foundation, Inc.
4
5 @include config.texi
6
7 @ifinfo
8 @format
9 START-INFO-DIR-ENTRY
10 * Binutils: (binutils). The GNU binary utilities.
11 * ar: (binutils)ar. Create, modify, and extract from archives
12 * nm: (binutils)nm. List symbols from object files
13 * objcopy: (binutils)objcopy. Copy and translate object files
14 * objdump: (binutils)objdump. Display information from object files
15 * ranlib: (binutils)ranlib. Generate index to archive contents
16 * readelf: (binutils)readelf. Display the contents of ELF format files.
17 * size: (binutils)size. List section sizes and total size
18 * strings: (binutils)strings. List printable strings from files
19 * strip: (binutils)strip. Discard symbols
20 * c++filt: (binutils)c++filt. Filter to demangle encoded C++ symbols
21 * cxxfilt: (binutils)c++filt. MS-DOS name for c++filt
22 * addr2line: (binutils)addr2line. Convert addresses to file and line
23 * nlmconv: (binutils)nlmconv. Converts object code into an NLM
24 * windres: (binutils)windres. Manipulate Windows resources
25 * dlltool: (binutils)dlltool. Create files needed to build and use DLLs
26 END-INFO-DIR-ENTRY
27 @end format
28 @end ifinfo
29
30 @ifinfo
31 @c man begin COPYRIGHT
32 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000,
33 2001, 2002, 2003 Free Software Foundation, Inc.
34
35 Permission is granted to copy, distribute and/or modify this document
36 under the terms of the GNU Free Documentation License, Version 1.1
37 or any later version published by the Free Software Foundation;
38 with no Invariant Sections, with no Front-Cover Texts, and with no
39 Back-Cover Texts. A copy of the license is included in the
40 section entitled ``GNU Free Documentation License''.
41
42 @c man end
43 @ignore
44 Permission is granted to process this file through TeX and print the
45 results, provided the printed document carries a copying permission
46 notice identical to this one except for the removal of this paragraph
47 (this paragraph not being relevant to the printed manual).
48
49 @end ignore
50 @end ifinfo
51
52 @synindex ky cp
53 @c
54 @c This file documents the GNU binary utilities "ar", "ld", "objcopy",
55 @c "objdump", "nm", "size", "strings", "strip", "readelf" and "ranlib".
56 @c
57 @c Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001,
58 @c 2002, 2003 Free Software Foundation, Inc.
59 @c
60 @c This text may be freely distributed under the terms of the GNU
61 @c Free Documentation License.
62 @c
63
64 @setchapternewpage odd
65 @settitle @sc{gnu} Binary Utilities
66 @titlepage
67 @finalout
68 @title The @sc{gnu} Binary Utilities
69 @subtitle Version @value{VERSION}
70 @sp 1
71 @subtitle May 1993
72 @author Roland H. Pesch
73 @author Jeffrey M. Osier
74 @author Cygnus Support
75 @page
76
77 @tex
78 {\parskip=0pt \hfill Cygnus Support\par \hfill
79 \TeX{}info \texinfoversion\par }
80 @end tex
81
82 @vskip 0pt plus 1filll
83 Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 1998, 2000, 2001,
84 2002, 2003 Free Software Foundation, Inc.
85
86 Permission is granted to copy, distribute and/or modify this document
87 under the terms of the GNU Free Documentation License, Version 1.1
88 or any later version published by the Free Software Foundation;
89 with no Invariant Sections, with no Front-Cover Texts, and with no
90 Back-Cover Texts. A copy of the license is included in the
91 section entitled ``GNU Free Documentation License''.
92
93 @end titlepage
94
95 @node Top
96 @top Introduction
97
98 @cindex version
99 This brief manual contains documentation for the @sc{gnu} binary
100 utilities (collectively version @value{VERSION}):
101
102 @iftex
103 @table @code
104 @item ar
105 Create, modify, and extract from archives
106
107 @item nm
108 List symbols from object files
109
110 @item objcopy
111 Copy and translate object files
112
113 @item objdump
114 Display information from object files
115
116 @item ranlib
117 Generate index to archive contents
118
119 @item readelf
120 Display the contents of ELF format files.
121
122 @item size
123 List file section sizes and total size
124
125 @item strings
126 List printable strings from files
127
128 @item strip
129 Discard symbols
130
131 @item c++filt
132 Demangle encoded C++ symbols (on MS-DOS, this program is named
133 @code{cxxfilt})
134
135 @item addr2line
136 Convert addresses into file names and line numbers
137
138 @item nlmconv
139 Convert object code into a Netware Loadable Module
140
141 @item windres
142 Manipulate Windows resources
143
144 @item dlltool
145 Create the files needed to build and use Dynamic Link Libraries
146 @end table
147 @end iftex
148
149 This document is distributed under the terms of the GNU Free
150 Documentation License. A copy of the license is included in the
151 section entitled "GNU Free Documentation License".
152
153 @menu
154 * ar:: Create, modify, and extract from archives
155 * nm:: List symbols from object files
156 * objcopy:: Copy and translate object files
157 * objdump:: Display information from object files
158 * ranlib:: Generate index to archive contents
159 * readelf:: Display the contents of ELF format files.
160 * size:: List section sizes and total size
161 * strings:: List printable strings from files
162 * strip:: Discard symbols
163 * c++filt:: Filter to demangle encoded C++ symbols
164 * cxxfilt: c++filt. MS-DOS name for c++filt
165 * addr2line:: Convert addresses to file and line
166 * nlmconv:: Converts object code into an NLM
167 * windres:: Manipulate Windows resources
168 * dlltool:: Create files needed to build and use DLLs
169 * Selecting The Target System:: How these utilities determine the target.
170 * Reporting Bugs:: Reporting Bugs
171 * GNU Free Documentation License:: GNU Free Documentation License
172 * Index:: Index
173 @end menu
174
175 @node ar
176 @chapter ar
177
178 @kindex ar
179 @cindex archives
180 @cindex collections of files
181
182 @c man title ar create, modify, and extract from archives
183
184 @smallexample
185 ar [-]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
186 ar -M [ <mri-script ]
187 @end smallexample
188
189 @c man begin DESCRIPTION ar
190
191 The @sc{gnu} @command{ar} program creates, modifies, and extracts from
192 archives. An @dfn{archive} is a single file holding a collection of
193 other files in a structure that makes it possible to retrieve
194 the original individual files (called @dfn{members} of the archive).
195
196 The original files' contents, mode (permissions), timestamp, owner, and
197 group are preserved in the archive, and can be restored on
198 extraction.
199
200 @cindex name length
201 @sc{gnu} @command{ar} can maintain archives whose members have names of any
202 length; however, depending on how @command{ar} is configured on your
203 system, a limit on member-name length may be imposed for compatibility
204 with archive formats maintained with other tools. If it exists, the
205 limit is often 15 characters (typical of formats related to a.out) or 16
206 characters (typical of formats related to coff).
207
208 @cindex libraries
209 @command{ar} is considered a binary utility because archives of this sort
210 are most often used as @dfn{libraries} holding commonly needed
211 subroutines.
212
213 @cindex symbol index
214 @command{ar} creates an index to the symbols defined in relocatable
215 object modules in the archive when you specify the modifier @samp{s}.
216 Once created, this index is updated in the archive whenever @command{ar}
217 makes a change to its contents (save for the @samp{q} update operation).
218 An archive with such an index speeds up linking to the library, and
219 allows routines in the library to call each other without regard to
220 their placement in the archive.
221
222 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index
223 table. If an archive lacks the table, another form of @command{ar} called
224 @command{ranlib} can be used to add just the table.
225
226 @cindex compatibility, @command{ar}
227 @cindex @command{ar} compatibility
228 @sc{gnu} @command{ar} is designed to be compatible with two different
229 facilities. You can control its activity using command-line options,
230 like the different varieties of @command{ar} on Unix systems; or, if you
231 specify the single command-line option @option{-M}, you can control it
232 with a script supplied via standard input, like the MRI ``librarian''
233 program.
234
235 @c man end
236
237 @menu
238 * ar cmdline:: Controlling @command{ar} on the command line
239 * ar scripts:: Controlling @command{ar} with a script
240 @end menu
241
242 @page
243 @node ar cmdline
244 @section Controlling @command{ar} on the Command Line
245
246 @smallexample
247 @c man begin SYNOPSIS ar
248 ar [@option{-X32_64}] [@option{-}]@var{p}[@var{mod} [@var{relpos}] [@var{count}]] @var{archive} [@var{member}@dots{}]
249 @c man end
250 @end smallexample
251
252 @cindex Unix compatibility, @command{ar}
253 When you use @command{ar} in the Unix style, @command{ar} insists on at least two
254 arguments to execute: one keyletter specifying the @emph{operation}
255 (optionally accompanied by other keyletters specifying
256 @emph{modifiers}), and the archive name to act on.
257
258 Most operations can also accept further @var{member} arguments,
259 specifying particular files to operate on.
260
261 @c man begin OPTIONS ar
262
263 @sc{gnu} @command{ar} allows you to mix the operation code @var{p} and modifier
264 flags @var{mod} in any order, within the first command-line argument.
265
266 If you wish, you may begin the first command-line argument with a
267 dash.
268
269 @cindex operations on archive
270 The @var{p} keyletter specifies what operation to execute; it may be
271 any of the following, but you must specify only one of them:
272
273 @table @samp
274 @item d
275 @cindex deleting from archive
276 @emph{Delete} modules from the archive. Specify the names of modules to
277 be deleted as @var{member}@dots{}; the archive is untouched if you
278 specify no files to delete.
279
280 If you specify the @samp{v} modifier, @command{ar} lists each module
281 as it is deleted.
282
283 @item m
284 @cindex moving in archive
285 Use this operation to @emph{move} members in an archive.
286
287 The ordering of members in an archive can make a difference in how
288 programs are linked using the library, if a symbol is defined in more
289 than one member.
290
291 If no modifiers are used with @code{m}, any members you name in the
292 @var{member} arguments are moved to the @emph{end} of the archive;
293 you can use the @samp{a}, @samp{b}, or @samp{i} modifiers to move them to a
294 specified place instead.
295
296 @item p
297 @cindex printing from archive
298 @emph{Print} the specified members of the archive, to the standard
299 output file. If the @samp{v} modifier is specified, show the member
300 name before copying its contents to standard output.
301
302 If you specify no @var{member} arguments, all the files in the archive are
303 printed.
304
305 @item q
306 @cindex quick append to archive
307 @emph{Quick append}; Historically, add the files @var{member}@dots{} to the end of
308 @var{archive}, without checking for replacement.
309
310 The modifiers @samp{a}, @samp{b}, and @samp{i} do @emph{not} affect this
311 operation; new members are always placed at the end of the archive.
312
313 The modifier @samp{v} makes @command{ar} list each file as it is appended.
314
315 Since the point of this operation is speed, the archive's symbol table
316 index is not updated, even if it already existed; you can use @samp{ar s} or
317 @command{ranlib} explicitly to update the symbol table index.
318
319 However, too many different systems assume quick append rebuilds the
320 index, so @sc{gnu} @command{ar} implements @samp{q} as a synonym for @samp{r}.
321
322 @item r
323 @cindex replacement in archive
324 Insert the files @var{member}@dots{} into @var{archive} (with
325 @emph{replacement}). This operation differs from @samp{q} in that any
326 previously existing members are deleted if their names match those being
327 added.
328
329 If one of the files named in @var{member}@dots{} does not exist, @command{ar}
330 displays an error message, and leaves undisturbed any existing members
331 of the archive matching that name.
332
333 By default, new members are added at the end of the file; but you may
334 use one of the modifiers @samp{a}, @samp{b}, or @samp{i} to request
335 placement relative to some existing member.
336
337 The modifier @samp{v} used with this operation elicits a line of
338 output for each file inserted, along with one of the letters @samp{a} or
339 @samp{r} to indicate whether the file was appended (no old member
340 deleted) or replaced.
341
342 @item t
343 @cindex contents of archive
344 Display a @emph{table} listing the contents of @var{archive}, or those
345 of the files listed in @var{member}@dots{} that are present in the
346 archive. Normally only the member name is shown; if you also want to
347 see the modes (permissions), timestamp, owner, group, and size, you can
348 request that by also specifying the @samp{v} modifier.
349
350 If you do not specify a @var{member}, all files in the archive
351 are listed.
352
353 @cindex repeated names in archive
354 @cindex name duplication in archive
355 If there is more than one file with the same name (say, @samp{fie}) in
356 an archive (say @samp{b.a}), @samp{ar t b.a fie} lists only the
357 first instance; to see them all, you must ask for a complete
358 listing---in our example, @samp{ar t b.a}.
359 @c WRS only; per Gumby, this is implementation-dependent, and in a more
360 @c recent case in fact works the other way.
361
362 @item x
363 @cindex extract from archive
364 @emph{Extract} members (named @var{member}) from the archive. You can
365 use the @samp{v} modifier with this operation, to request that
366 @command{ar} list each name as it extracts it.
367
368 If you do not specify a @var{member}, all files in the archive
369 are extracted.
370
371 @end table
372
373 A number of modifiers (@var{mod}) may immediately follow the @var{p}
374 keyletter, to specify variations on an operation's behavior:
375
376 @table @samp
377 @item a
378 @cindex relative placement in archive
379 Add new files @emph{after} an existing member of the
380 archive. If you use the modifier @samp{a}, the name of an existing archive
381 member must be present as the @var{relpos} argument, before the
382 @var{archive} specification.
383
384 @item b
385 Add new files @emph{before} an existing member of the
386 archive. If you use the modifier @samp{b}, the name of an existing archive
387 member must be present as the @var{relpos} argument, before the
388 @var{archive} specification. (same as @samp{i}).
389
390 @item c
391 @cindex creating archives
392 @emph{Create} the archive. The specified @var{archive} is always
393 created if it did not exist, when you request an update. But a warning is
394 issued unless you specify in advance that you expect to create it, by
395 using this modifier.
396
397 @item f
398 Truncate names in the archive. @sc{gnu} @command{ar} will normally permit file
399 names of any length. This will cause it to create archives which are
400 not compatible with the native @command{ar} program on some systems. If
401 this is a concern, the @samp{f} modifier may be used to truncate file
402 names when putting them in the archive.
403
404 @item i
405 Insert new files @emph{before} an existing member of the
406 archive. If you use the modifier @samp{i}, the name of an existing archive
407 member must be present as the @var{relpos} argument, before the
408 @var{archive} specification. (same as @samp{b}).
409
410 @item l
411 This modifier is accepted but not used.
412 @c whaffor ar l modifier??? presumably compat; with
413 @c what???---doc@@cygnus.com, 25jan91
414
415 @item N
416 Uses the @var{count} parameter. This is used if there are multiple
417 entries in the archive with the same name. Extract or delete instance
418 @var{count} of the given name from the archive.
419
420 @item o
421 @cindex dates in archive
422 Preserve the @emph{original} dates of members when extracting them. If
423 you do not specify this modifier, files extracted from the archive
424 are stamped with the time of extraction.
425
426 @item P
427 Use the full path name when matching names in the archive. @sc{gnu}
428 @command{ar} can not create an archive with a full path name (such archives
429 are not POSIX complaint), but other archive creators can. This option
430 will cause @sc{gnu} @command{ar} to match file names using a complete path
431 name, which can be convenient when extracting a single file from an
432 archive created by another tool.
433
434 @item s
435 @cindex writing archive index
436 Write an object-file index into the archive, or update an existing one,
437 even if no other change is made to the archive. You may use this modifier
438 flag either with any operation, or alone. Running @samp{ar s} on an
439 archive is equivalent to running @samp{ranlib} on it.
440
441 @item S
442 @cindex not writing archive index
443 Do not generate an archive symbol table. This can speed up building a
444 large library in several steps. The resulting archive can not be used
445 with the linker. In order to build a symbol table, you must omit the
446 @samp{S} modifier on the last execution of @samp{ar}, or you must run
447 @samp{ranlib} on the archive.
448
449 @item u
450 @cindex updating an archive
451 Normally, @samp{ar r}@dots{} inserts all files
452 listed into the archive. If you would like to insert @emph{only} those
453 of the files you list that are newer than existing members of the same
454 names, use this modifier. The @samp{u} modifier is allowed only for the
455 operation @samp{r} (replace). In particular, the combination @samp{qu} is
456 not allowed, since checking the timestamps would lose any speed
457 advantage from the operation @samp{q}.
458
459 @item v
460 This modifier requests the @emph{verbose} version of an operation. Many
461 operations display additional information, such as filenames processed,
462 when the modifier @samp{v} is appended.
463
464 @item V
465 This modifier shows the version number of @command{ar}.
466 @end table
467
468 @command{ar} ignores an initial option spelt @samp{-X32_64}, for
469 compatibility with AIX. The behaviour produced by this option is the
470 default for @sc{gnu} @command{ar}. @command{ar} does not support any of the other
471 @samp{-X} options; in particular, it does not support @option{-X32}
472 which is the default for AIX @command{ar}.
473
474 @c man end
475
476 @ignore
477 @c man begin SEEALSO ar
478 nm(1), ranlib(1), and the Info entries for @file{binutils}.
479 @c man end
480 @end ignore
481
482 @node ar scripts
483 @section Controlling @command{ar} with a Script
484
485 @smallexample
486 ar -M [ <@var{script} ]
487 @end smallexample
488
489 @cindex MRI compatibility, @command{ar}
490 @cindex scripts, @command{ar}
491 If you use the single command-line option @samp{-M} with @command{ar}, you
492 can control its operation with a rudimentary command language. This
493 form of @command{ar} operates interactively if standard input is coming
494 directly from a terminal. During interactive use, @command{ar} prompts for
495 input (the prompt is @samp{AR >}), and continues executing even after
496 errors. If you redirect standard input to a script file, no prompts are
497 issued, and @command{ar} abandons execution (with a nonzero exit code)
498 on any error.
499
500 The @command{ar} command language is @emph{not} designed to be equivalent
501 to the command-line options; in fact, it provides somewhat less control
502 over archives. The only purpose of the command language is to ease the
503 transition to @sc{gnu} @command{ar} for developers who already have scripts
504 written for the MRI ``librarian'' program.
505
506 The syntax for the @command{ar} command language is straightforward:
507 @itemize @bullet
508 @item
509 commands are recognized in upper or lower case; for example, @code{LIST}
510 is the same as @code{list}. In the following descriptions, commands are
511 shown in upper case for clarity.
512
513 @item
514 a single command may appear on each line; it is the first word on the
515 line.
516
517 @item
518 empty lines are allowed, and have no effect.
519
520 @item
521 comments are allowed; text after either of the characters @samp{*}
522 or @samp{;} is ignored.
523
524 @item
525 Whenever you use a list of names as part of the argument to an @command{ar}
526 command, you can separate the individual names with either commas or
527 blanks. Commas are shown in the explanations below, for clarity.
528
529 @item
530 @samp{+} is used as a line continuation character; if @samp{+} appears
531 at the end of a line, the text on the following line is considered part
532 of the current command.
533 @end itemize
534
535 Here are the commands you can use in @command{ar} scripts, or when using
536 @command{ar} interactively. Three of them have special significance:
537
538 @code{OPEN} or @code{CREATE} specify a @dfn{current archive}, which is
539 a temporary file required for most of the other commands.
540
541 @code{SAVE} commits the changes so far specified by the script. Prior
542 to @code{SAVE}, commands affect only the temporary copy of the current
543 archive.
544
545 @table @code
546 @item ADDLIB @var{archive}
547 @itemx ADDLIB @var{archive} (@var{module}, @var{module}, @dots{} @var{module})
548 Add all the contents of @var{archive} (or, if specified, each named
549 @var{module} from @var{archive}) to the current archive.
550
551 Requires prior use of @code{OPEN} or @code{CREATE}.
552
553 @item ADDMOD @var{member}, @var{member}, @dots{} @var{member}
554 @c FIXME! w/Replacement?? If so, like "ar r @var{archive} @var{names}"
555 @c else like "ar q..."
556 Add each named @var{member} as a module in the current archive.
557
558 Requires prior use of @code{OPEN} or @code{CREATE}.
559
560 @item CLEAR
561 Discard the contents of the current archive, canceling the effect of
562 any operations since the last @code{SAVE}. May be executed (with no
563 effect) even if no current archive is specified.
564
565 @item CREATE @var{archive}
566 Creates an archive, and makes it the current archive (required for many
567 other commands). The new archive is created with a temporary name; it
568 is not actually saved as @var{archive} until you use @code{SAVE}.
569 You can overwrite existing archives; similarly, the contents of any
570 existing file named @var{archive} will not be destroyed until @code{SAVE}.
571
572 @item DELETE @var{module}, @var{module}, @dots{} @var{module}
573 Delete each listed @var{module} from the current archive; equivalent to
574 @samp{ar -d @var{archive} @var{module} @dots{} @var{module}}.
575
576 Requires prior use of @code{OPEN} or @code{CREATE}.
577
578 @item DIRECTORY @var{archive} (@var{module}, @dots{} @var{module})
579 @itemx DIRECTORY @var{archive} (@var{module}, @dots{} @var{module}) @var{outputfile}
580 List each named @var{module} present in @var{archive}. The separate
581 command @code{VERBOSE} specifies the form of the output: when verbose
582 output is off, output is like that of @samp{ar -t @var{archive}
583 @var{module}@dots{}}. When verbose output is on, the listing is like
584 @samp{ar -tv @var{archive} @var{module}@dots{}}.
585
586 Output normally goes to the standard output stream; however, if you
587 specify @var{outputfile} as a final argument, @command{ar} directs the
588 output to that file.
589
590 @item END
591 Exit from @command{ar}, with a @code{0} exit code to indicate successful
592 completion. This command does not save the output file; if you have
593 changed the current archive since the last @code{SAVE} command, those
594 changes are lost.
595
596 @item EXTRACT @var{module}, @var{module}, @dots{} @var{module}
597 Extract each named @var{module} from the current archive, writing them
598 into the current directory as separate files. Equivalent to @samp{ar -x
599 @var{archive} @var{module}@dots{}}.
600
601 Requires prior use of @code{OPEN} or @code{CREATE}.
602
603 @ignore
604 @c FIXME Tokens but no commands???
605 @item FULLDIR
606
607 @item HELP
608 @end ignore
609
610 @item LIST
611 Display full contents of the current archive, in ``verbose'' style
612 regardless of the state of @code{VERBOSE}. The effect is like @samp{ar
613 tv @var{archive}}. (This single command is a @sc{gnu} @command{ar}
614 enhancement, rather than present for MRI compatibility.)
615
616 Requires prior use of @code{OPEN} or @code{CREATE}.
617
618 @item OPEN @var{archive}
619 Opens an existing archive for use as the current archive (required for
620 many other commands). Any changes as the result of subsequent commands
621 will not actually affect @var{archive} until you next use @code{SAVE}.
622
623 @item REPLACE @var{module}, @var{module}, @dots{} @var{module}
624 In the current archive, replace each existing @var{module} (named in
625 the @code{REPLACE} arguments) from files in the current working directory.
626 To execute this command without errors, both the file, and the module in
627 the current archive, must exist.
628
629 Requires prior use of @code{OPEN} or @code{CREATE}.
630
631 @item VERBOSE
632 Toggle an internal flag governing the output from @code{DIRECTORY}.
633 When the flag is on, @code{DIRECTORY} output matches output from
634 @samp{ar -tv }@dots{}.
635
636 @item SAVE
637 Commit your changes to the current archive, and actually save it as a
638 file with the name specified in the last @code{CREATE} or @code{OPEN}
639 command.
640
641 Requires prior use of @code{OPEN} or @code{CREATE}.
642
643 @end table
644
645 @iftex
646 @node ld
647 @chapter ld
648 @cindex linker
649 @kindex ld
650 The @sc{gnu} linker @command{ld} is now described in a separate manual.
651 @xref{Top,, Overview,, Using LD: the @sc{gnu} linker}.
652 @end iftex
653
654 @node nm
655 @chapter nm
656 @cindex symbols
657 @kindex nm
658
659 @c man title nm list symbols from object files
660
661 @smallexample
662 @c man begin SYNOPSIS nm
663 nm [@option{-a}|@option{--debug-syms}] [@option{-g}|@option{--extern-only}]
664 [@option{-B}] [@option{-C}|@option{--demangle}[=@var{style}]] [@option{-D}|@option{--dynamic}]
665 [@option{-S}|@option{--print-size}] [@option{-s}|@option{--print-armap}]
666 [@option{-A}|@option{-o}|@option{--print-file-name}]
667 [@option{-n}|@option{-v}|@option{--numeric-sort}] [@option{-p}|@option{--no-sort}]
668 [@option{-r}|@option{--reverse-sort}] [@option{--size-sort}] [@option{-u}|@option{--undefined-only}]
669 [@option{-t} @var{radix}|@option{--radix=}@var{radix}] [@option{-P}|@option{--portability}]
670 [@option{--target=}@var{bfdname}] [@option{-f}@var{format}|@option{--format=}@var{format}]
671 [@option{--defined-only}] [@option{-l}|@option{--line-numbers}] [@option{--no-demangle}]
672 [@option{-V}|@option{--version}] [@option{-X 32_64}] [@option{--help}] [@var{objfile}@dots{}]
673 @c man end
674 @end smallexample
675
676 @c man begin DESCRIPTION nm
677 @sc{gnu} @command{nm} lists the symbols from object files @var{objfile}@dots{}.
678 If no object files are listed as arguments, @command{nm} assumes the file
679 @file{a.out}.
680
681 For each symbol, @command{nm} shows:
682
683 @itemize @bullet
684 @item
685 The symbol value, in the radix selected by options (see below), or
686 hexadecimal by default.
687
688 @item
689 The symbol type. At least the following types are used; others are, as
690 well, depending on the object file format. If lowercase, the symbol is
691 local; if uppercase, the symbol is global (external).
692
693 @c Some more detail on exactly what these symbol types are used for
694 @c would be nice.
695 @table @code
696 @item A
697 The symbol's value is absolute, and will not be changed by further
698 linking.
699
700 @item B
701 The symbol is in the uninitialized data section (known as BSS).
702
703 @item C
704 The symbol is common. Common symbols are uninitialized data. When
705 linking, multiple common symbols may appear with the same name. If the
706 symbol is defined anywhere, the common symbols are treated as undefined
707 references.
708 @ifclear man
709 For more details on common symbols, see the discussion of
710 --warn-common in @ref{Options,,Linker options,ld.info,The GNU linker}.
711 @end ifclear
712
713 @item D
714 The symbol is in the initialized data section.
715
716 @item G
717 The symbol is in an initialized data section for small objects. Some
718 object file formats permit more efficient access to small data objects,
719 such as a global int variable as opposed to a large global array.
720
721 @item I
722 The symbol is an indirect reference to another symbol. This is a @sc{gnu}
723 extension to the a.out object file format which is rarely used.
724
725 @item N
726 The symbol is a debugging symbol.
727
728 @item R
729 The symbol is in a read only data section.
730
731 @item S
732 The symbol is in an uninitialized data section for small objects.
733
734 @item T
735 The symbol is in the text (code) section.
736
737 @item U
738 The symbol is undefined.
739
740 @item V
741 The symbol is a weak object. When a weak defined symbol is linked with
742 a normal defined symbol, the normal defined symbol is used with no error.
743 When a weak undefined symbol is linked and the symbol is not defined,
744 the value of the weak symbol becomes zero with no error.
745
746 @item W
747 The symbol is a weak symbol that has not been specifically tagged as a
748 weak object symbol. When a weak defined symbol is linked with a normal
749 defined symbol, the normal defined symbol is used with no error.
750 When a weak undefined symbol is linked and the symbol is not defined,
751 the value of the weak symbol becomes zero with no error.
752
753 @item -
754 The symbol is a stabs symbol in an a.out object file. In this case, the
755 next values printed are the stabs other field, the stabs desc field, and
756 the stab type. Stabs symbols are used to hold debugging information.
757 @ifclear man
758 For more information, see @ref{Top,Stabs,Stabs Overview,stabs.info, The
759 ``stabs'' debug format}.
760 @end ifclear
761
762 @item ?
763 The symbol type is unknown, or object file format specific.
764 @end table
765
766 @item
767 The symbol name.
768 @end itemize
769
770 @c man end
771
772 @c man begin OPTIONS nm
773 The long and short forms of options, shown here as alternatives, are
774 equivalent.
775
776 @table @env
777 @item -A
778 @itemx -o
779 @itemx --print-file-name
780 @cindex input file name
781 @cindex file name
782 @cindex source file name
783 Precede each symbol by the name of the input file (or archive member)
784 in which it was found, rather than identifying the input file once only,
785 before all of its symbols.
786
787 @item -a
788 @itemx --debug-syms
789 @cindex debugging symbols
790 Display all symbols, even debugger-only symbols; normally these are not
791 listed.
792
793 @item -B
794 @cindex @command{nm} format
795 @cindex @command{nm} compatibility
796 The same as @option{--format=bsd} (for compatibility with the MIPS @command{nm}).
797
798 @item -C
799 @itemx --demangle[=@var{style}]
800 @cindex demangling in nm
801 Decode (@dfn{demangle}) low-level symbol names into user-level names.
802 Besides removing any initial underscore prepended by the system, this
803 makes C++ function names readable. Different compilers have different
804 mangling styles. The optional demangling style argument can be used to
805 choose an appropriate demangling style for your compiler. @xref{c++filt},
806 for more information on demangling.
807
808 @item --no-demangle
809 Do not demangle low-level symbol names. This is the default.
810
811 @item -D
812 @itemx --dynamic
813 @cindex dynamic symbols
814 Display the dynamic symbols rather than the normal symbols. This is
815 only meaningful for dynamic objects, such as certain types of shared
816 libraries.
817
818 @item -f @var{format}
819 @itemx --format=@var{format}
820 @cindex @command{nm} format
821 @cindex @command{nm} compatibility
822 Use the output format @var{format}, which can be @code{bsd},
823 @code{sysv}, or @code{posix}. The default is @code{bsd}.
824 Only the first character of @var{format} is significant; it can be
825 either upper or lower case.
826
827 @item -g
828 @itemx --extern-only
829 @cindex external symbols
830 Display only external symbols.
831
832 @item -l
833 @itemx --line-numbers
834 @cindex symbol line numbers
835 For each symbol, use debugging information to try to find a filename and
836 line number. For a defined symbol, look for the line number of the
837 address of the symbol. For an undefined symbol, look for the line
838 number of a relocation entry which refers to the symbol. If line number
839 information can be found, print it after the other symbol information.
840
841 @item -n
842 @itemx -v
843 @itemx --numeric-sort
844 Sort symbols numerically by their addresses, rather than alphabetically
845 by their names.
846
847 @item -p
848 @itemx --no-sort
849 @cindex sorting symbols
850 Do not bother to sort the symbols in any order; print them in the order
851 encountered.
852
853 @item -P
854 @itemx --portability
855 Use the POSIX.2 standard output format instead of the default format.
856 Equivalent to @samp{-f posix}.
857
858 @item -S
859 @itemx --print-size
860 Print size, not the value, of defined symbols for the @code{bsd} output format.
861
862 @item -s
863 @itemx --print-armap
864 @cindex symbol index, listing
865 When listing symbols from archive members, include the index: a mapping
866 (stored in the archive by @command{ar} or @command{ranlib}) of which modules
867 contain definitions for which names.
868
869 @item -r
870 @itemx --reverse-sort
871 Reverse the order of the sort (whether numeric or alphabetic); let the
872 last come first.
873
874 @item --size-sort
875 Sort symbols by size. The size is computed as the difference between
876 the value of the symbol and the value of the symbol with the next higher
877 value. If the @code{bsd} output format is used the size of the symbol
878 is printed, rather than the value, and @samp{-S} must be used in order
879 both size and value to be printed.
880
881 @item -t @var{radix}
882 @itemx --radix=@var{radix}
883 Use @var{radix} as the radix for printing the symbol values. It must be
884 @samp{d} for decimal, @samp{o} for octal, or @samp{x} for hexadecimal.
885
886 @item --target=@var{bfdname}
887 @cindex object code format
888 Specify an object code format other than your system's default format.
889 @xref{Target Selection}, for more information.
890
891 @item -u
892 @itemx --undefined-only
893 @cindex external symbols
894 @cindex undefined symbols
895 Display only undefined symbols (those external to each object file).
896
897 @item --defined-only
898 @cindex external symbols
899 @cindex undefined symbols
900 Display only defined symbols for each object file.
901
902 @item -V
903 @itemx --version
904 Show the version number of @command{nm} and exit.
905
906 @item -X
907 This option is ignored for compatibility with the AIX version of
908 @command{nm}. It takes one parameter which must be the string
909 @option{32_64}. The default mode of AIX @command{nm} corresponds
910 to @option{-X 32}, which is not supported by @sc{gnu} @command{nm}.
911
912 @item --help
913 Show a summary of the options to @command{nm} and exit.
914 @end table
915
916 @c man end
917
918 @ignore
919 @c man begin SEEALSO nm
920 ar(1), objdump(1), ranlib(1), and the Info entries for @file{binutils}.
921 @c man end
922 @end ignore
923
924 @node objcopy
925 @chapter objcopy
926
927 @c man title objcopy copy and translate object files
928
929 @smallexample
930 @c man begin SYNOPSIS objcopy
931 objcopy [@option{-F} @var{bfdname}|@option{--target=}@var{bfdname}]
932 [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
933 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
934 [@option{-B} @var{bfdarch}|@option{--binary-architecture=}@var{bfdarch}]
935 [@option{-S}|@option{--strip-all}]
936 [@option{-g}|@option{--strip-debug}]
937 [@option{-K} @var{symbolname}|@option{--keep-symbol=}@var{symbolname}]
938 [@option{-N} @var{symbolname}|@option{--strip-symbol=}@var{symbolname}]
939 [@option{-G} @var{symbolname}|@option{--keep-global-symbol=}@var{symbolname}]
940 [@option{-L} @var{symbolname}|@option{--localize-symbol=}@var{symbolname}]
941 [@option{-W} @var{symbolname}|@option{--weaken-symbol=}@var{symbolname}]
942 [@option{-x}|@option{--discard-all}]
943 [@option{-X}|@option{--discard-locals}]
944 [@option{-b} @var{byte}|@option{--byte=}@var{byte}]
945 [@option{-i} @var{interleave}|@option{--interleave=}@var{interleave}]
946 [@option{-j} @var{sectionname}|@option{--only-section=}@var{sectionname}]
947 [@option{-R} @var{sectionname}|@option{--remove-section=}@var{sectionname}]
948 [@option{-p}|@option{--preserve-dates}]
949 [@option{--debugging}]
950 [@option{--gap-fill=}@var{val}]
951 [@option{--pad-to=}@var{address}]
952 [@option{--set-start=}@var{val}]
953 [@option{--adjust-start=}@var{incr}]
954 [@option{--change-addresses=}@var{incr}]
955 [@option{--change-section-address} @var{section}@{=,+,-@}@var{val}]
956 [@option{--change-section-lma} @var{section}@{=,+,-@}@var{val}]
957 [@option{--change-section-vma} @var{section}@{=,+,-@}@var{val}]
958 [@option{--change-warnings}] [@option{--no-change-warnings}]
959 [@option{--set-section-flags} @var{section}=@var{flags}]
960 [@option{--add-section} @var{sectionname}=@var{filename}]
961 [@option{--rename-section} @var{oldname}=@var{newname}[,@var{flags}]]
962 [@option{--change-leading-char}] [@option{--remove-leading-char}]
963 [@option{--srec-len=}@var{ival}] [@option{--srec-forceS3}]
964 [@option{--redefine-sym} @var{old}=@var{new}]
965 [@option{--redefine-syms=}@var{filename}]
966 [@option{--weaken}]
967 [@option{--keep-symbols=}@var{filename}]
968 [@option{--strip-symbols=}@var{filename}]
969 [@option{--keep-global-symbols=}@var{filename}]
970 [@option{--localize-symbols=}@var{filename}]
971 [@option{--weaken-symbols=}@var{filename}]
972 [@option{--alt-machine-code=}@var{index}]
973 [@option{--prefix-symbols=}@var{string}]
974 [@option{--prefix-sections=}@var{string}]
975 [@option{--prefix-alloc-sections=}@var{string}]
976 [@option{--add-gnu-debuglink=}@var{path-to-file}]
977 [@option{--only-keep-debug}]
978 [@option{-v}|@option{--verbose}]
979 [@option{-V}|@option{--version}]
980 [@option{--help}] [@option{--info}]
981 @var{infile} [@var{outfile}]
982 @c man end
983 @end smallexample
984
985 @c man begin DESCRIPTION objcopy
986 The @sc{gnu} @command{objcopy} utility copies the contents of an object
987 file to another. @command{objcopy} uses the @sc{gnu} @sc{bfd} Library to
988 read and write the object files. It can write the destination object
989 file in a format different from that of the source object file. The
990 exact behavior of @command{objcopy} is controlled by command-line options.
991 Note that @command{objcopy} should be able to copy a fully linked file
992 between any two formats. However, copying a relocatable object file
993 between any two formats may not work as expected.
994
995 @command{objcopy} creates temporary files to do its translations and
996 deletes them afterward. @command{objcopy} uses @sc{bfd} to do all its
997 translation work; it has access to all the formats described in @sc{bfd}
998 and thus is able to recognize most formats without being told
999 explicitly. @xref{BFD,,BFD,ld.info,Using LD}.
1000
1001 @command{objcopy} can be used to generate S-records by using an output
1002 target of @samp{srec} (e.g., use @samp{-O srec}).
1003
1004 @command{objcopy} can be used to generate a raw binary file by using an
1005 output target of @samp{binary} (e.g., use @option{-O binary}). When
1006 @command{objcopy} generates a raw binary file, it will essentially produce
1007 a memory dump of the contents of the input object file. All symbols and
1008 relocation information will be discarded. The memory dump will start at
1009 the load address of the lowest section copied into the output file.
1010
1011 When generating an S-record or a raw binary file, it may be helpful to
1012 use @option{-S} to remove sections containing debugging information. In
1013 some cases @option{-R} will be useful to remove sections which contain
1014 information that is not needed by the binary file.
1015
1016 Note---@command{objcopy} is not able to change the endianness of its input
1017 files. If the input format has an endianness (some formats do not),
1018 @command{objcopy} can only copy the inputs into file formats that have the
1019 same endianness or which have no endianness (e.g., @samp{srec}).
1020
1021 @c man end
1022
1023 @c man begin OPTIONS objcopy
1024
1025 @table @env
1026 @item @var{infile}
1027 @itemx @var{outfile}
1028 The input and output files, respectively.
1029 If you do not specify @var{outfile}, @command{objcopy} creates a
1030 temporary file and destructively renames the result with
1031 the name of @var{infile}.
1032
1033 @item -I @var{bfdname}
1034 @itemx --input-target=@var{bfdname}
1035 Consider the source file's object format to be @var{bfdname}, rather than
1036 attempting to deduce it. @xref{Target Selection}, for more information.
1037
1038 @item -O @var{bfdname}
1039 @itemx --output-target=@var{bfdname}
1040 Write the output file using the object format @var{bfdname}.
1041 @xref{Target Selection}, for more information.
1042
1043 @item -F @var{bfdname}
1044 @itemx --target=@var{bfdname}
1045 Use @var{bfdname} as the object format for both the input and the output
1046 file; i.e., simply transfer data from source to destination with no
1047 translation. @xref{Target Selection}, for more information.
1048
1049 @item -B @var{bfdarch}
1050 @itemx --binary-architecture=@var{bfdarch}
1051 Useful when transforming a raw binary input file into an object file.
1052 In this case the output architecture can be set to @var{bfdarch}. This
1053 option will be ignored if the input file has a known @var{bfdarch}. You
1054 can access this binary data inside a program by referencing the special
1055 symbols that are created by the conversion process. These symbols are
1056 called _binary_@var{objfile}_start, _binary_@var{objfile}_end and
1057 _binary_@var{objfile}_size. e.g. you can transform a picture file into
1058 an object file and then access it in your code using these symbols.
1059
1060 @item -j @var{sectionname}
1061 @itemx --only-section=@var{sectionname}
1062 Copy only the named section from the input file to the output file.
1063 This option may be given more than once. Note that using this option
1064 inappropriately may make the output file unusable.
1065
1066 @item -R @var{sectionname}
1067 @itemx --remove-section=@var{sectionname}
1068 Remove any section named @var{sectionname} from the output file. This
1069 option may be given more than once. Note that using this option
1070 inappropriately may make the output file unusable.
1071
1072 @item -S
1073 @itemx --strip-all
1074 Do not copy relocation and symbol information from the source file.
1075
1076 @item -g
1077 @itemx --strip-debug
1078 Do not copy debugging symbols or sections from the source file.
1079
1080 @item --strip-unneeded
1081 Strip all symbols that are not needed for relocation processing.
1082
1083 @item -K @var{symbolname}
1084 @itemx --keep-symbol=@var{symbolname}
1085 Copy only symbol @var{symbolname} from the source file. This option may
1086 be given more than once.
1087
1088 @item -N @var{symbolname}
1089 @itemx --strip-symbol=@var{symbolname}
1090 Do not copy symbol @var{symbolname} from the source file. This option
1091 may be given more than once.
1092
1093 @item -G @var{symbolname}
1094 @itemx --keep-global-symbol=@var{symbolname}
1095 Keep only symbol @var{symbolname} global. Make all other symbols local
1096 to the file, so that they are not visible externally. This option may
1097 be given more than once.
1098
1099 @item -L @var{symbolname}
1100 @itemx --localize-symbol=@var{symbolname}
1101 Make symbol @var{symbolname} local to the file, so that it is not
1102 visible externally. This option may be given more than once.
1103
1104 @item -W @var{symbolname}
1105 @itemx --weaken-symbol=@var{symbolname}
1106 Make symbol @var{symbolname} weak. This option may be given more than once.
1107
1108 @item -x
1109 @itemx --discard-all
1110 Do not copy non-global symbols from the source file.
1111 @c FIXME any reason to prefer "non-global" to "local" here?
1112
1113 @item -X
1114 @itemx --discard-locals
1115 Do not copy compiler-generated local symbols.
1116 (These usually start with @samp{L} or @samp{.}.)
1117
1118 @item -b @var{byte}
1119 @itemx --byte=@var{byte}
1120 Keep only every @var{byte}th byte of the input file (header data is not
1121 affected). @var{byte} can be in the range from 0 to @var{interleave}-1,
1122 where @var{interleave} is given by the @option{-i} or @option{--interleave}
1123 option, or the default of 4. This option is useful for creating files
1124 to program @sc{rom}. It is typically used with an @code{srec} output
1125 target.
1126
1127 @item -i @var{interleave}
1128 @itemx --interleave=@var{interleave}
1129 Only copy one out of every @var{interleave} bytes. Select which byte to
1130 copy with the @option{-b} or @option{--byte} option. The default is 4.
1131 @command{objcopy} ignores this option if you do not specify either @option{-b} or
1132 @option{--byte}.
1133
1134 @item -p
1135 @itemx --preserve-dates
1136 Set the access and modification dates of the output file to be the same
1137 as those of the input file.
1138
1139 @item --debugging
1140 Convert debugging information, if possible. This is not the default
1141 because only certain debugging formats are supported, and the
1142 conversion process can be time consuming.
1143
1144 @item --gap-fill @var{val}
1145 Fill gaps between sections with @var{val}. This operation applies to
1146 the @emph{load address} (LMA) of the sections. It is done by increasing
1147 the size of the section with the lower address, and filling in the extra
1148 space created with @var{val}.
1149
1150 @item --pad-to @var{address}
1151 Pad the output file up to the load address @var{address}. This is
1152 done by increasing the size of the last section. The extra space is
1153 filled in with the value specified by @option{--gap-fill} (default zero).
1154
1155 @item --set-start @var{val}
1156 Set the start address of the new file to @var{val}. Not all object file
1157 formats support setting the start address.
1158
1159 @item --change-start @var{incr}
1160 @itemx --adjust-start @var{incr}
1161 @cindex changing start address
1162 Change the start address by adding @var{incr}. Not all object file
1163 formats support setting the start address.
1164
1165 @item --change-addresses @var{incr}
1166 @itemx --adjust-vma @var{incr}
1167 @cindex changing object addresses
1168 Change the VMA and LMA addresses of all sections, as well as the start
1169 address, by adding @var{incr}. Some object file formats do not permit
1170 section addresses to be changed arbitrarily. Note that this does not
1171 relocate the sections; if the program expects sections to be loaded at a
1172 certain address, and this option is used to change the sections such
1173 that they are loaded at a different address, the program may fail.
1174
1175 @item --change-section-address @var{section}@{=,+,-@}@var{val}
1176 @itemx --adjust-section-vma @var{section}@{=,+,-@}@var{val}
1177 @cindex changing section address
1178 Set or change both the VMA address and the LMA address of the named
1179 @var{section}. If @samp{=} is used, the section address is set to
1180 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1181 section address. See the comments under @option{--change-addresses},
1182 above. If @var{section} does not exist in the input file, a warning will
1183 be issued, unless @option{--no-change-warnings} is used.
1184
1185 @item --change-section-lma @var{section}@{=,+,-@}@var{val}
1186 @cindex changing section LMA
1187 Set or change the LMA address of the named @var{section}. The LMA
1188 address is the address where the section will be loaded into memory at
1189 program load time. Normally this is the same as the VMA address, which
1190 is the address of the section at program run time, but on some systems,
1191 especially those where a program is held in ROM, the two can be
1192 different. If @samp{=} is used, the section address is set to
1193 @var{val}. Otherwise, @var{val} is added to or subtracted from the
1194 section address. See the comments under @option{--change-addresses},
1195 above. If @var{section} does not exist in the input file, a warning
1196 will be issued, unless @option{--no-change-warnings} is used.
1197
1198 @item --change-section-vma @var{section}@{=,+,-@}@var{val}
1199 @cindex changing section VMA
1200 Set or change the VMA address of the named @var{section}. The VMA
1201 address is the address where the section will be located once the
1202 program has started executing. Normally this is the same as the LMA
1203 address, which is the address where the section will be loaded into
1204 memory, but on some systems, especially those where a program is held in
1205 ROM, the two can be different. If @samp{=} is used, the section address
1206 is set to @var{val}. Otherwise, @var{val} is added to or subtracted
1207 from the section address. See the comments under
1208 @option{--change-addresses}, above. If @var{section} does not exist in
1209 the input file, a warning will be issued, unless
1210 @option{--no-change-warnings} is used.
1211
1212 @item --change-warnings
1213 @itemx --adjust-warnings
1214 If @option{--change-section-address} or @option{--change-section-lma} or
1215 @option{--change-section-vma} is used, and the named section does not
1216 exist, issue a warning. This is the default.
1217
1218 @item --no-change-warnings
1219 @itemx --no-adjust-warnings
1220 Do not issue a warning if @option{--change-section-address} or
1221 @option{--adjust-section-lma} or @option{--adjust-section-vma} is used, even
1222 if the named section does not exist.
1223
1224 @item --set-section-flags @var{section}=@var{flags}
1225 Set the flags for the named section. The @var{flags} argument is a
1226 comma separated string of flag names. The recognized names are
1227 @samp{alloc}, @samp{contents}, @samp{load}, @samp{noload},
1228 @samp{readonly}, @samp{code}, @samp{data}, @samp{rom}, @samp{share}, and
1229 @samp{debug}. You can set the @samp{contents} flag for a section which
1230 does not have contents, but it is not meaningful to clear the
1231 @samp{contents} flag of a section which does have contents--just remove
1232 the section instead. Not all flags are meaningful for all object file
1233 formats.
1234
1235 @item --add-section @var{sectionname}=@var{filename}
1236 Add a new section named @var{sectionname} while copying the file. The
1237 contents of the new section are taken from the file @var{filename}. The
1238 size of the section will be the size of the file. This option only
1239 works on file formats which can support sections with arbitrary names.
1240
1241 @item --rename-section @var{oldname}=@var{newname}[,@var{flags}]
1242 Rename a section from @var{oldname} to @var{newname}, optionally
1243 changing the section's flags to @var{flags} in the process. This has
1244 the advantage over usng a linker script to perform the rename in that
1245 the output stays as an object file and does not become a linked
1246 executable.
1247
1248 This option is particularly helpful when the input format is binary,
1249 since this will always create a section called .data. If for example,
1250 you wanted instead to create a section called .rodata containing binary
1251 data you could use the following command line to achieve it:
1252
1253 @smallexample
1254 objcopy -I binary -O <output_format> -B <architecture> \
1255 --rename-section .data=.rodata,alloc,load,readonly,data,contents \
1256 <input_binary_file> <output_object_file>
1257 @end smallexample
1258
1259 @item --change-leading-char
1260 Some object file formats use special characters at the start of
1261 symbols. The most common such character is underscore, which compilers
1262 often add before every symbol. This option tells @command{objcopy} to
1263 change the leading character of every symbol when it converts between
1264 object file formats. If the object file formats use the same leading
1265 character, this option has no effect. Otherwise, it will add a
1266 character, or remove a character, or change a character, as
1267 appropriate.
1268
1269 @item --remove-leading-char
1270 If the first character of a global symbol is a special symbol leading
1271 character used by the object file format, remove the character. The
1272 most common symbol leading character is underscore. This option will
1273 remove a leading underscore from all global symbols. This can be useful
1274 if you want to link together objects of different file formats with
1275 different conventions for symbol names. This is different from
1276 @option{--change-leading-char} because it always changes the symbol name
1277 when appropriate, regardless of the object file format of the output
1278 file.
1279
1280 @item --srec-len=@var{ival}
1281 Meaningful only for srec output. Set the maximum length of the Srecords
1282 being produced to @var{ival}. This length covers both address, data and
1283 crc fields.
1284
1285 @item --srec-forceS3
1286 Meaningful only for srec output. Avoid generation of S1/S2 records,
1287 creating S3-only record format.
1288
1289 @item --redefine-sym @var{old}=@var{new}
1290 Change the name of a symbol @var{old}, to @var{new}. This can be useful
1291 when one is trying link two things together for which you have no
1292 source, and there are name collisions.
1293
1294 @item --redefine-syms=@var{filename}
1295 Apply @option{--redefine-sym} to each symbol pair "@var{old} @var{new}"
1296 listed in the file @var{filename}. @var{filename} is simply a flat file,
1297 with one symbol pair per line. Line comments may be introduced by the hash
1298 character. This option may be given more than once.
1299
1300 @item --weaken
1301 Change all global symbols in the file to be weak. This can be useful
1302 when building an object which will be linked against other objects using
1303 the @option{-R} option to the linker. This option is only effective when
1304 using an object file format which supports weak symbols.
1305
1306 @item --keep-symbols=@var{filename}
1307 Apply @option{--keep-symbol} option to each symbol listed in the file
1308 @var{filename}. @var{filename} is simply a flat file, with one symbol
1309 name per line. Line comments may be introduced by the hash character.
1310 This option may be given more than once.
1311
1312 @item --strip-symbols=@var{filename}
1313 Apply @option{--strip-symbol} option to each symbol listed in the file
1314 @var{filename}. @var{filename} is simply a flat file, with one symbol
1315 name per line. Line comments may be introduced by the hash character.
1316 This option may be given more than once.
1317
1318 @item --keep-global-symbols=@var{filename}
1319 Apply @option{--keep-global-symbol} option to each symbol listed in the
1320 file @var{filename}. @var{filename} is simply a flat file, with one
1321 symbol name per line. Line comments may be introduced by the hash
1322 character. This option may be given more than once.
1323
1324 @item --localize-symbols=@var{filename}
1325 Apply @option{--localize-symbol} option to each symbol listed in the file
1326 @var{filename}. @var{filename} is simply a flat file, with one symbol
1327 name per line. Line comments may be introduced by the hash character.
1328 This option may be given more than once.
1329
1330 @item --weaken-symbols=@var{filename}
1331 Apply @option{--weaken-symbol} option to each symbol listed in the file
1332 @var{filename}. @var{filename} is simply a flat file, with one symbol
1333 name per line. Line comments may be introduced by the hash character.
1334 This option may be given more than once.
1335
1336 @item --alt-machine-code=@var{index}
1337 If the output architecture has alternate machine codes, use the
1338 @var{index}th code instead of the default one. This is useful in case
1339 a machine is assigned an official code and the tool-chain adopts the
1340 new code, but other applications still depend on the original code
1341 being used.
1342
1343 @item --prefix-symbols=@var{string}
1344 Prefix all symbols in the output file with @var{string}.
1345
1346 @item --prefix-sections=@var{string}
1347 Prefix all section names in the output file with @var{string}.
1348
1349 @item --prefix-alloc-sections=@var{string}
1350 Prefix all the names of all allocated sections in the output file with
1351 @var{string}.
1352
1353 @item --add-gnu-debuglink=@var{path-to-file}
1354 Creates a .gnu_debuglink section which contains a reference to @var{path-to-file}
1355 and adds it to the output file.
1356
1357 @item --only-keep-debug
1358 Strip a file, removing any sections that would be stripped by
1359 @option{--strip-debug} and leaving the debugging sections.
1360
1361 The intention is that this option will be used in conjunction with
1362 @option{--add-gnu-debuglink} to create a two part executable. One a
1363 stripped binary which will occupy less space in RAM and in a
1364 distribution and the second a debugging information file which is only
1365 needed if debugging abilities are required. The suggested procedure
1366 to create these files is as follows:
1367
1368 @enumerate
1369 @item Link the executable as normal. Assuming that is is called
1370 @code{foo} then...
1371 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
1372 create a file containing the debugging info.
1373 @item Run @code{objcopy --strip-debug foo} to create a
1374 stripped executable.
1375 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
1376 to add a link to the debugging info into the stripped executable.
1377 @end enumerate
1378
1379 Note - the choice of @code{.dbg} as an extension for the debug info
1380 file is arbitrary. Also the @code{--only-keep-debug} step is
1381 optional. You could instead do this:
1382
1383 @enumerate
1384 @item Link the executable as normal.
1385 @item Copy @code{foo} to @code{foo.full}
1386 @item Run @code{objcopy --strip-debug foo}
1387 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
1388 @end enumerate
1389
1390 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
1391 full executable. It does not have to be a file created by the
1392 @option{--only-keep-debug} switch.
1393
1394 @item -V
1395 @itemx --version
1396 Show the version number of @command{objcopy}.
1397
1398 @item -v
1399 @itemx --verbose
1400 Verbose output: list all object files modified. In the case of
1401 archives, @samp{objcopy -V} lists all members of the archive.
1402
1403 @item --help
1404 Show a summary of the options to @command{objcopy}.
1405
1406 @item --info
1407 Display a list showing all architectures and object formats available.
1408 @end table
1409
1410 @c man end
1411
1412 @ignore
1413 @c man begin SEEALSO objcopy
1414 ld(1), objdump(1), and the Info entries for @file{binutils}.
1415 @c man end
1416 @end ignore
1417
1418 @node objdump
1419 @chapter objdump
1420
1421 @cindex object file information
1422 @kindex objdump
1423
1424 @c man title objdump display information from object files.
1425
1426 @smallexample
1427 @c man begin SYNOPSIS objdump
1428 objdump [@option{-a}|@option{--archive-headers}]
1429 [@option{-b} @var{bfdname}|@option{--target=@var{bfdname}}]
1430 [@option{-C}|@option{--demangle}[=@var{style}] ]
1431 [@option{-d}|@option{--disassemble}]
1432 [@option{-D}|@option{--disassemble-all}]
1433 [@option{-z}|@option{--disassemble-zeroes}]
1434 [@option{-EB}|@option{-EL}|@option{--endian=}@{big | little @}]
1435 [@option{-f}|@option{--file-headers}]
1436 [@option{--file-start-context}]
1437 [@option{-g}|@option{--debugging}]
1438 [@option{-e}|@option{--debugging-tags}]
1439 [@option{-h}|@option{--section-headers}|@option{--headers}]
1440 [@option{-i}|@option{--info}]
1441 [@option{-j} @var{section}|@option{--section=}@var{section}]
1442 [@option{-l}|@option{--line-numbers}]
1443 [@option{-S}|@option{--source}]
1444 [@option{-m} @var{machine}|@option{--architecture=}@var{machine}]
1445 [@option{-M} @var{options}|@option{--disassembler-options=}@var{options}]
1446 [@option{-p}|@option{--private-headers}]
1447 [@option{-r}|@option{--reloc}]
1448 [@option{-R}|@option{--dynamic-reloc}]
1449 [@option{-s}|@option{--full-contents}]
1450 [@option{-G}|@option{--stabs}]
1451 [@option{-t}|@option{--syms}]
1452 [@option{-T}|@option{--dynamic-syms}]
1453 [@option{-x}|@option{--all-headers}]
1454 [@option{-w}|@option{--wide}]
1455 [@option{--start-address=}@var{address}]
1456 [@option{--stop-address=}@var{address}]
1457 [@option{--prefix-addresses}]
1458 [@option{--[no-]show-raw-insn}]
1459 [@option{--adjust-vma=}@var{offset}]
1460 [@option{-V}|@option{--version}]
1461 [@option{-H}|@option{--help}]
1462 @var{objfile}@dots{}
1463 @c man end
1464 @end smallexample
1465
1466 @c man begin DESCRIPTION objdump
1467
1468 @command{objdump} displays information about one or more object files.
1469 The options control what particular information to display. This
1470 information is mostly useful to programmers who are working on the
1471 compilation tools, as opposed to programmers who just want their
1472 program to compile and work.
1473
1474 @var{objfile}@dots{} are the object files to be examined. When you
1475 specify archives, @command{objdump} shows information on each of the member
1476 object files.
1477
1478 @c man end
1479
1480 @c man begin OPTIONS objdump
1481
1482 The long and short forms of options, shown here as alternatives, are
1483 equivalent. At least one option from the list
1484 @option{-a,-d,-D,-e,-f,-g,-G,-h,-H,-p,-r,-R,-s,-S,-t,-T,-V,-x} must be given.
1485
1486 @table @env
1487 @item -a
1488 @itemx --archive-header
1489 @cindex archive headers
1490 If any of the @var{objfile} files are archives, display the archive
1491 header information (in a format similar to @samp{ls -l}). Besides the
1492 information you could list with @samp{ar tv}, @samp{objdump -a} shows
1493 the object file format of each archive member.
1494
1495 @item --adjust-vma=@var{offset}
1496 @cindex section addresses in objdump
1497 @cindex VMA in objdump
1498 When dumping information, first add @var{offset} to all the section
1499 addresses. This is useful if the section addresses do not correspond to
1500 the symbol table, which can happen when putting sections at particular
1501 addresses when using a format which can not represent section addresses,
1502 such as a.out.
1503
1504 @item -b @var{bfdname}
1505 @itemx --target=@var{bfdname}
1506 @cindex object code format
1507 Specify that the object-code format for the object files is
1508 @var{bfdname}. This option may not be necessary; @var{objdump} can
1509 automatically recognize many formats.
1510
1511 For example,
1512 @example
1513 objdump -b oasys -m vax -h fu.o
1514 @end example
1515 @noindent
1516 displays summary information from the section headers (@option{-h}) of
1517 @file{fu.o}, which is explicitly identified (@option{-m}) as a VAX object
1518 file in the format produced by Oasys compilers. You can list the
1519 formats available with the @option{-i} option.
1520 @xref{Target Selection}, for more information.
1521
1522 @item -C
1523 @itemx --demangle[=@var{style}]
1524 @cindex demangling in objdump
1525 Decode (@dfn{demangle}) low-level symbol names into user-level names.
1526 Besides removing any initial underscore prepended by the system, this
1527 makes C++ function names readable. Different compilers have different
1528 mangling styles. The optional demangling style argument can be used to
1529 choose an appropriate demangling style for your compiler. @xref{c++filt},
1530 for more information on demangling.
1531
1532 @item -g
1533 @itemx --debugging
1534 Display debugging information. This attempts to parse debugging
1535 information stored in the file and print it out using a C like syntax.
1536 Only certain types of debugging information have been implemented.
1537 Some other types are supported by @command{readelf -w}.
1538 @xref{readelf}.
1539
1540 @item -e
1541 @itemx --debugging-tags
1542 Like @option{-g}, but the information is generated in a format compatible
1543 with ctags tool.
1544
1545 @item -d
1546 @itemx --disassemble
1547 @cindex disassembling object code
1548 @cindex machine instructions
1549 Display the assembler mnemonics for the machine instructions from
1550 @var{objfile}. This option only disassembles those sections which are
1551 expected to contain instructions.
1552
1553 @item -D
1554 @itemx --disassemble-all
1555 Like @option{-d}, but disassemble the contents of all sections, not just
1556 those expected to contain instructions.
1557
1558 @item --prefix-addresses
1559 When disassembling, print the complete address on each line. This is
1560 the older disassembly format.
1561
1562 @item -EB
1563 @itemx -EL
1564 @itemx --endian=@{big|little@}
1565 @cindex endianness
1566 @cindex disassembly endianness
1567 Specify the endianness of the object files. This only affects
1568 disassembly. This can be useful when disassembling a file format which
1569 does not describe endianness information, such as S-records.
1570
1571 @item -f
1572 @itemx --file-headers
1573 @cindex object file header
1574 Display summary information from the overall header of
1575 each of the @var{objfile} files.
1576
1577 @item --file-start-context
1578 @cindex source code context
1579 Specify that when displaying interlisted source code/disassembly
1580 (assumes @option{-S}) from a file that has not yet been displayed, extend the
1581 context to the start of the file.
1582
1583 @item -h
1584 @itemx --section-headers
1585 @itemx --headers
1586 @cindex section headers
1587 Display summary information from the section headers of the
1588 object file.
1589
1590 File segments may be relocated to nonstandard addresses, for example by
1591 using the @option{-Ttext}, @option{-Tdata}, or @option{-Tbss} options to
1592 @command{ld}. However, some object file formats, such as a.out, do not
1593 store the starting address of the file segments. In those situations,
1594 although @command{ld} relocates the sections correctly, using @samp{objdump
1595 -h} to list the file section headers cannot show the correct addresses.
1596 Instead, it shows the usual addresses, which are implicit for the
1597 target.
1598
1599 @item -H
1600 @itemx --help
1601 Print a summary of the options to @command{objdump} and exit.
1602
1603 @item -i
1604 @itemx --info
1605 @cindex architectures available
1606 @cindex object formats available
1607 Display a list showing all architectures and object formats available
1608 for specification with @option{-b} or @option{-m}.
1609
1610 @item -j @var{name}
1611 @itemx --section=@var{name}
1612 @cindex section information
1613 Display information only for section @var{name}.
1614
1615 @item -l
1616 @itemx --line-numbers
1617 @cindex source filenames for object files
1618 Label the display (using debugging information) with the filename and
1619 source line numbers corresponding to the object code or relocs shown.
1620 Only useful with @option{-d}, @option{-D}, or @option{-r}.
1621
1622 @item -m @var{machine}
1623 @itemx --architecture=@var{machine}
1624 @cindex architecture
1625 @cindex disassembly architecture
1626 Specify the architecture to use when disassembling object files. This
1627 can be useful when disassembling object files which do not describe
1628 architecture information, such as S-records. You can list the available
1629 architectures with the @option{-i} option.
1630
1631 @item -M @var{options}
1632 @itemx --disassembler-options=@var{options}
1633 Pass target specific information to the disassembler. Only supported on
1634 some targets. If it is necessary to specify more than one
1635 disassembler option then multiple @option{-M} options can be used or
1636 can be placed together into a comma separated list.
1637
1638 If the target is an ARM architecture then this switch can be used to
1639 select which register name set is used during disassembler. Specifying
1640 @option{-M reg-name-std} (the default) will select the register names as
1641 used in ARM's instruction set documentation, but with register 13 called
1642 'sp', register 14 called 'lr' and register 15 called 'pc'. Specifying
1643 @option{-M reg-names-apcs} will select the name set used by the ARM
1644 Procedure Call Standard, whilst specifying @option{-M reg-names-raw} will
1645 just use @samp{r} followed by the register number.
1646
1647 There are also two variants on the APCS register naming scheme enabled
1648 by @option{-M reg-names-atpcs} and @option{-M reg-names-special-atpcs} which
1649 use the ARM/Thumb Procedure Call Standard naming conventions. (Either
1650 with the normal register names or the special register names).
1651
1652 This option can also be used for ARM architectures to force the
1653 disassembler to interpret all instructions as Thumb instructions by
1654 using the switch @option{--disassembler-options=force-thumb}. This can be
1655 useful when attempting to disassemble thumb code produced by other
1656 compilers.
1657
1658 For the x86, some of the options duplicate functions of the @option{-m}
1659 switch, but allow finer grained control. Multiple selections from the
1660 following may be specified as a comma separated string.
1661 @option{x86-64}, @option{i386} and @option{i8086} select disassembly for
1662 the given architecture. @option{intel} and @option{att} select between
1663 intel syntax mode and AT&T syntax mode. @option{addr32},
1664 @option{addr16}, @option{data32} and @option{data16} specify the default
1665 address size and operand size. These four options will be overridden if
1666 @option{x86-64}, @option{i386} or @option{i8086} appear later in the
1667 option string. Lastly, @option{suffix}, when in AT&T mode,
1668 instructs the disassembler to print a mnemonic suffix even when the
1669 suffix could be inferred by the operands.
1670
1671 For PPC, @option{booke}, @option{booke32} and @option{booke64} select
1672 disassembly of BookE instructions. @option{32} and @option{64} select
1673 PowerPC and PowerPC64 disassembly, respectively.
1674
1675 For MIPS, this option controls the printing of register names in
1676 disassembled instructions. Multiple selections from the
1677 following may be specified as a comma separated string, and invalid
1678 options are ignored:
1679
1680 @table @code
1681 @item gpr-names=@var{ABI}
1682 Print GPR (general-purpose register) names as appropriate
1683 for the specified ABI. By default, GPR names are selected according to
1684 the ABI of the binary being disassembled.
1685
1686 @item fpr-names=@var{ABI}
1687 Print FPR (floating-point register) names as
1688 appropriate for the specified ABI. By default, FPR numbers are printed
1689 rather than names.
1690
1691 @item cp0-names=@var{ARCH}
1692 Print CP0 (system control coprocessor; coprocessor 0) register names
1693 as appropriate for the CPU or architecture specified by
1694 @var{ARCH}. By default, CP0 register names are selected according to
1695 the architecture and CPU of the binary being disassembled.
1696
1697 @item hwr-names=@var{ARCH}
1698 Print HWR (hardware register, used by the @code{rdhwr} instruction) names
1699 as appropriate for the CPU or architecture specified by
1700 @var{ARCH}. By default, HWR names are selected according to
1701 the architecture and CPU of the binary being disassembled.
1702
1703 @item reg-names=@var{ABI}
1704 Print GPR and FPR names as appropriate for the selected ABI.
1705
1706 @item reg-names=@var{ARCH}
1707 Print CPU-specific register names (CP0 register and HWR names)
1708 as appropriate for the selected CPU or architecture.
1709 @end table
1710
1711 For any of the options listed above, @var{ABI} or
1712 @var{ARCH} may be specified as @samp{numeric} to have numbers printed
1713 rather than names, for the selected types of registers.
1714 You can list the available values of @var{ABI} and @var{ARCH} using
1715 the @option{--help} option.
1716
1717 @item -p
1718 @itemx --private-headers
1719 Print information that is specific to the object file format. The exact
1720 information printed depends upon the object file format. For some
1721 object file formats, no additional information is printed.
1722
1723 @item -r
1724 @itemx --reloc
1725 @cindex relocation entries, in object file
1726 Print the relocation entries of the file. If used with @option{-d} or
1727 @option{-D}, the relocations are printed interspersed with the
1728 disassembly.
1729
1730 @item -R
1731 @itemx --dynamic-reloc
1732 @cindex dynamic relocation entries, in object file
1733 Print the dynamic relocation entries of the file. This is only
1734 meaningful for dynamic objects, such as certain types of shared
1735 libraries.
1736
1737 @item -s
1738 @itemx --full-contents
1739 @cindex sections, full contents
1740 @cindex object file sections
1741 Display the full contents of any sections requested. By default all
1742 non-empty sections are displayed.
1743
1744 @item -S
1745 @itemx --source
1746 @cindex source disassembly
1747 @cindex disassembly, with source
1748 Display source code intermixed with disassembly, if possible. Implies
1749 @option{-d}.
1750
1751 @item --show-raw-insn
1752 When disassembling instructions, print the instruction in hex as well as
1753 in symbolic form. This is the default except when
1754 @option{--prefix-addresses} is used.
1755
1756 @item --no-show-raw-insn
1757 When disassembling instructions, do not print the instruction bytes.
1758 This is the default when @option{--prefix-addresses} is used.
1759
1760 @item -G
1761 @itemx --stabs
1762 @cindex stab
1763 @cindex .stab
1764 @cindex debug symbols
1765 @cindex ELF object file format
1766 Display the full contents of any sections requested. Display the
1767 contents of the .stab and .stab.index and .stab.excl sections from an
1768 ELF file. This is only useful on systems (such as Solaris 2.0) in which
1769 @code{.stab} debugging symbol-table entries are carried in an ELF
1770 section. In most other file formats, debugging symbol-table entries are
1771 interleaved with linkage symbols, and are visible in the @option{--syms}
1772 output.
1773 @ifclear man
1774 For more information on stabs symbols, see @ref{Top,Stabs,Stabs
1775 Overview,stabs.info, The ``stabs'' debug format}.
1776 @end ifclear
1777
1778 @item --start-address=@var{address}
1779 @cindex start-address
1780 Start displaying data at the specified address. This affects the output
1781 of the @option{-d}, @option{-r} and @option{-s} options.
1782
1783 @item --stop-address=@var{address}
1784 @cindex stop-address
1785 Stop displaying data at the specified address. This affects the output
1786 of the @option{-d}, @option{-r} and @option{-s} options.
1787
1788 @item -t
1789 @itemx --syms
1790 @cindex symbol table entries, printing
1791 Print the symbol table entries of the file.
1792 This is similar to the information provided by the @samp{nm} program.
1793
1794 @item -T
1795 @itemx --dynamic-syms
1796 @cindex dynamic symbol table entries, printing
1797 Print the dynamic symbol table entries of the file. This is only
1798 meaningful for dynamic objects, such as certain types of shared
1799 libraries. This is similar to the information provided by the @samp{nm}
1800 program when given the @option{-D} (@option{--dynamic}) option.
1801
1802 @item -V
1803 @itemx --version
1804 Print the version number of @command{objdump} and exit.
1805
1806 @item -x
1807 @itemx --all-headers
1808 @cindex all header information, object file
1809 @cindex header information, all
1810 Display all available header information, including the symbol table and
1811 relocation entries. Using @option{-x} is equivalent to specifying all of
1812 @option{-a -f -h -r -t}.
1813
1814 @item -w
1815 @itemx --wide
1816 @cindex wide output, printing
1817 Format some lines for output devices that have more than 80 columns.
1818 Also do not truncate symbol names when they are displayed.
1819
1820 @item -z
1821 @itemx --disassemble-zeroes
1822 Normally the disassembly output will skip blocks of zeroes. This
1823 option directs the disassembler to disassemble those blocks, just like
1824 any other data.
1825 @end table
1826
1827 @c man end
1828
1829 @ignore
1830 @c man begin SEEALSO objdump
1831 nm(1), readelf(1), and the Info entries for @file{binutils}.
1832 @c man end
1833 @end ignore
1834
1835 @node ranlib
1836 @chapter ranlib
1837
1838 @kindex ranlib
1839 @cindex archive contents
1840 @cindex symbol index
1841
1842 @c man title ranlib generate index to archive.
1843
1844 @smallexample
1845 @c man begin SYNOPSIS ranlib
1846 ranlib [@option{-vV}] @var{archive}
1847 @c man end
1848 @end smallexample
1849
1850 @c man begin DESCRIPTION ranlib
1851
1852 @command{ranlib} generates an index to the contents of an archive and
1853 stores it in the archive. The index lists each symbol defined by a
1854 member of an archive that is a relocatable object file.
1855
1856 You may use @samp{nm -s} or @samp{nm --print-armap} to list this index.
1857
1858 An archive with such an index speeds up linking to the library and
1859 allows routines in the library to call each other without regard to
1860 their placement in the archive.
1861
1862 The @sc{gnu} @command{ranlib} program is another form of @sc{gnu} @command{ar}; running
1863 @command{ranlib} is completely equivalent to executing @samp{ar -s}.
1864 @xref{ar}.
1865
1866 @c man end
1867
1868 @c man begin OPTIONS ranlib
1869
1870 @table @env
1871 @item -v
1872 @itemx -V
1873 @itemx --version
1874 Show the version number of @command{ranlib}.
1875 @end table
1876
1877 @c man end
1878
1879 @ignore
1880 @c man begin SEEALSO ranlib
1881 ar(1), nm(1), and the Info entries for @file{binutils}.
1882 @c man end
1883 @end ignore
1884
1885 @node size
1886 @chapter size
1887
1888 @kindex size
1889 @cindex section sizes
1890
1891 @c man title size list section sizes and total size.
1892
1893 @smallexample
1894 @c man begin SYNOPSIS size
1895 size [@option{-A}|@option{-B}|@option{--format=}@var{compatibility}]
1896 [@option{--help}]
1897 [@option{-d}|@option{-o}|@option{-x}|@option{--radix=}@var{number}]
1898 [@option{-t}|@option{--totals}]
1899 [@option{--target=}@var{bfdname}] [@option{-V}|@option{--version}]
1900 [@var{objfile}@dots{}]
1901 @c man end
1902 @end smallexample
1903
1904 @c man begin DESCRIPTION size
1905
1906 The @sc{gnu} @command{size} utility lists the section sizes---and the total
1907 size---for each of the object or archive files @var{objfile} in its
1908 argument list. By default, one line of output is generated for each
1909 object file or each module in an archive.
1910
1911 @var{objfile}@dots{} are the object files to be examined.
1912 If none are specified, the file @code{a.out} will be used.
1913
1914 @c man end
1915
1916 @c man begin OPTIONS size
1917
1918 The command line options have the following meanings:
1919
1920 @table @env
1921 @item -A
1922 @itemx -B
1923 @itemx --format=@var{compatibility}
1924 @cindex @command{size} display format
1925 Using one of these options, you can choose whether the output from @sc{gnu}
1926 @command{size} resembles output from System V @command{size} (using @option{-A},
1927 or @option{--format=sysv}), or Berkeley @command{size} (using @option{-B}, or
1928 @option{--format=berkeley}). The default is the one-line format similar to
1929 Berkeley's.
1930 @c Bonus for doc-source readers: you can also say --format=strange (or
1931 @c anything else that starts with 's') for sysv, and --format=boring (or
1932 @c anything else that starts with 'b') for Berkeley.
1933
1934 Here is an example of the Berkeley (default) format of output from
1935 @command{size}:
1936 @smallexample
1937 $ size --format=Berkeley ranlib size
1938 text data bss dec hex filename
1939 294880 81920 11592 388392 5ed28 ranlib
1940 294880 81920 11888 388688 5ee50 size
1941 @end smallexample
1942
1943 @noindent
1944 This is the same data, but displayed closer to System V conventions:
1945
1946 @smallexample
1947 $ size --format=SysV ranlib size
1948 ranlib :
1949 section size addr
1950 .text 294880 8192
1951 .data 81920 303104
1952 .bss 11592 385024
1953 Total 388392
1954
1955
1956 size :
1957 section size addr
1958 .text 294880 8192
1959 .data 81920 303104
1960 .bss 11888 385024
1961 Total 388688
1962 @end smallexample
1963
1964 @item --help
1965 Show a summary of acceptable arguments and options.
1966
1967 @item -d
1968 @itemx -o
1969 @itemx -x
1970 @itemx --radix=@var{number}
1971 @cindex @command{size} number format
1972 @cindex radix for section sizes
1973 Using one of these options, you can control whether the size of each
1974 section is given in decimal (@option{-d}, or @option{--radix=10}); octal
1975 (@option{-o}, or @option{--radix=8}); or hexadecimal (@option{-x}, or
1976 @option{--radix=16}). In @option{--radix=@var{number}}, only the three
1977 values (8, 10, 16) are supported. The total size is always given in two
1978 radices; decimal and hexadecimal for @option{-d} or @option{-x} output, or
1979 octal and hexadecimal if you're using @option{-o}.
1980
1981 @item -t
1982 @itemx --totals
1983 Show totals of all objects listed (Berkeley format listing mode only).
1984
1985 @item --target=@var{bfdname}
1986 @cindex object code format
1987 Specify that the object-code format for @var{objfile} is
1988 @var{bfdname}. This option may not be necessary; @command{size} can
1989 automatically recognize many formats.
1990 @xref{Target Selection}, for more information.
1991
1992 @item -V
1993 @itemx --version
1994 Display the version number of @command{size}.
1995 @end table
1996
1997 @c man end
1998
1999 @ignore
2000 @c man begin SEEALSO size
2001 ar(1), objdump(1), readelf(1), and the Info entries for @file{binutils}.
2002 @c man end
2003 @end ignore
2004
2005 @node strings
2006 @chapter strings
2007 @kindex strings
2008 @cindex listings strings
2009 @cindex printing strings
2010 @cindex strings, printing
2011
2012 @c man title strings print the strings of printable characters in files.
2013
2014 @smallexample
2015 @c man begin SYNOPSIS strings
2016 strings [@option{-afov}] [@option{-}@var{min-len}]
2017 [@option{-n} @var{min-len}] [@option{--bytes=}@var{min-len}]
2018 [@option{-t} @var{radix}] [@option{--radix=}@var{radix}]
2019 [@option{-e} @var{encoding}] [@option{--encoding=}@var{encoding}]
2020 [@option{-}] [@option{--all}] [@option{--print-file-name}]
2021 [@option{--target=}@var{bfdname}]
2022 [@option{--help}] [@option{--version}] @var{file}@dots{}
2023 @c man end
2024 @end smallexample
2025
2026 @c man begin DESCRIPTION strings
2027
2028 For each @var{file} given, @sc{gnu} @command{strings} prints the printable
2029 character sequences that are at least 4 characters long (or the number
2030 given with the options below) and are followed by an unprintable
2031 character. By default, it only prints the strings from the initialized
2032 and loaded sections of object files; for other types of files, it prints
2033 the strings from the whole file.
2034
2035 @command{strings} is mainly useful for determining the contents of non-text
2036 files.
2037
2038 @c man end
2039
2040 @c man begin OPTIONS strings
2041
2042 @table @env
2043 @item -a
2044 @itemx --all
2045 @itemx -
2046 Do not scan only the initialized and loaded sections of object files;
2047 scan the whole files.
2048
2049 @item -f
2050 @itemx --print-file-name
2051 Print the name of the file before each string.
2052
2053 @item --help
2054 Print a summary of the program usage on the standard output and exit.
2055
2056 @item -@var{min-len}
2057 @itemx -n @var{min-len}
2058 @itemx --bytes=@var{min-len}
2059 Print sequences of characters that are at least @var{min-len} characters
2060 long, instead of the default 4.
2061
2062 @item -o
2063 Like @samp{-t o}. Some other versions of @command{strings} have @option{-o}
2064 act like @samp{-t d} instead. Since we can not be compatible with both
2065 ways, we simply chose one.
2066
2067 @item -t @var{radix}
2068 @itemx --radix=@var{radix}
2069 Print the offset within the file before each string. The single
2070 character argument specifies the radix of the offset---@samp{o} for
2071 octal, @samp{x} for hexadecimal, or @samp{d} for decimal.
2072
2073 @item -e @var{encoding}
2074 @itemx --encoding=@var{encoding}
2075 Select the character encoding of the strings that are to be found.
2076 Possible values for @var{encoding} are: @samp{s} = single-7-bit-byte
2077 characters (ASCII, ISO 8859, etc., default), @samp{S} =
2078 single-8-bit-byte characters, @samp{b} = 16-bit bigendian, @samp{l} =
2079 16-bit littleendian, @samp{B} = 32-bit bigendian, @samp{L} = 32-bit
2080 littleendian. Useful for finding wide character strings.
2081
2082 @item --target=@var{bfdname}
2083 @cindex object code format
2084 Specify an object code format other than your system's default format.
2085 @xref{Target Selection}, for more information.
2086
2087 @item -v
2088 @itemx --version
2089 Print the program version number on the standard output and exit.
2090 @end table
2091
2092 @c man end
2093
2094 @ignore
2095 @c man begin SEEALSO strings
2096 ar(1), nm(1), objdump(1), ranlib(1), readelf(1)
2097 and the Info entries for @file{binutils}.
2098 @c man end
2099 @end ignore
2100
2101 @node strip
2102 @chapter strip
2103
2104 @kindex strip
2105 @cindex removing symbols
2106 @cindex discarding symbols
2107 @cindex symbols, discarding
2108
2109 @c man title strip Discard symbols from object files.
2110
2111 @smallexample
2112 @c man begin SYNOPSIS strip
2113 strip [@option{-F} @var{bfdname} |@option{--target=}@var{bfdname}]
2114 [@option{-I} @var{bfdname} |@option{--input-target=}@var{bfdname}]
2115 [@option{-O} @var{bfdname} |@option{--output-target=}@var{bfdname}]
2116 [@option{-s}|@option{--strip-all}]
2117 [@option{-S}|@option{-g}|@option{-d}|@option{--strip-debug}]
2118 [@option{-K} @var{symbolname} |@option{--keep-symbol=}@var{symbolname}]
2119 [@option{-N} @var{symbolname} |@option{--strip-symbol=}@var{symbolname}]
2120 [@option{-x}|@option{--discard-all}] [@option{-X} |@option{--discard-locals}]
2121 [@option{-R} @var{sectionname} |@option{--remove-section=}@var{sectionname}]
2122 [@option{-o} @var{file}] [@option{-p}|@option{--preserve-dates}]
2123 [@option{--only-keep-debug}]
2124 [@option{-v} |@option{--verbose}] [@option{-V}|@option{--version}]
2125 [@option{--help}] [@option{--info}]
2126 @var{objfile}@dots{}
2127 @c man end
2128 @end smallexample
2129
2130 @c man begin DESCRIPTION strip
2131
2132 @sc{gnu} @command{strip} discards all symbols from object files
2133 @var{objfile}. The list of object files may include archives.
2134 At least one object file must be given.
2135
2136 @command{strip} modifies the files named in its argument,
2137 rather than writing modified copies under different names.
2138
2139 @c man end
2140
2141 @c man begin OPTIONS strip
2142
2143 @table @env
2144 @item -F @var{bfdname}
2145 @itemx --target=@var{bfdname}
2146 Treat the original @var{objfile} as a file with the object
2147 code format @var{bfdname}, and rewrite it in the same format.
2148 @xref{Target Selection}, for more information.
2149
2150 @item --help
2151 Show a summary of the options to @command{strip} and exit.
2152
2153 @item --info
2154 Display a list showing all architectures and object formats available.
2155
2156 @item -I @var{bfdname}
2157 @itemx --input-target=@var{bfdname}
2158 Treat the original @var{objfile} as a file with the object
2159 code format @var{bfdname}.
2160 @xref{Target Selection}, for more information.
2161
2162 @item -O @var{bfdname}
2163 @itemx --output-target=@var{bfdname}
2164 Replace @var{objfile} with a file in the output format @var{bfdname}.
2165 @xref{Target Selection}, for more information.
2166
2167 @item -R @var{sectionname}
2168 @itemx --remove-section=@var{sectionname}
2169 Remove any section named @var{sectionname} from the output file. This
2170 option may be given more than once. Note that using this option
2171 inappropriately may make the output file unusable.
2172
2173 @item -s
2174 @itemx --strip-all
2175 Remove all symbols.
2176
2177 @item -g
2178 @itemx -S
2179 @itemx -d
2180 @itemx --strip-debug
2181 Remove debugging symbols only.
2182
2183 @item --strip-unneeded
2184 Remove all symbols that are not needed for relocation processing.
2185
2186 @item -K @var{symbolname}
2187 @itemx --keep-symbol=@var{symbolname}
2188 Keep only symbol @var{symbolname} from the source file. This option may
2189 be given more than once.
2190
2191 @item -N @var{symbolname}
2192 @itemx --strip-symbol=@var{symbolname}
2193 Remove symbol @var{symbolname} from the source file. This option may be
2194 given more than once, and may be combined with strip options other than
2195 @option{-K}.
2196
2197 @item -o @var{file}
2198 Put the stripped output in @var{file}, rather than replacing the
2199 existing file. When this argument is used, only one @var{objfile}
2200 argument may be specified.
2201
2202 @item -p
2203 @itemx --preserve-dates
2204 Preserve the access and modification dates of the file.
2205
2206 @item -x
2207 @itemx --discard-all
2208 Remove non-global symbols.
2209
2210 @item -X
2211 @itemx --discard-locals
2212 Remove compiler-generated local symbols.
2213 (These usually start with @samp{L} or @samp{.}.)
2214
2215 @item --only-keep-debug
2216 Strip a file, removing any sections that would be stripped by
2217 @option{--strip-debug} and leaving the debugging sections.
2218
2219 The intention is that this option will be used in conjunction with
2220 @option{--add-gnu-debuglink} to create a two part executable. One a
2221 stripped binary which will occupy less space in RAM and in a
2222 distribution and the second a debugging information file which is only
2223 needed if debugging abilities are required. The suggested procedure
2224 to create these files is as follows:
2225
2226 @enumerate
2227 @item Link the executable as normal. Assuming that is is called
2228 @code{foo} then...
2229 @item Run @code{objcopy --only-keep-debug foo foo.dbg} to
2230 create a file containing the debugging info.
2231 @item Run @code{objcopy --strip-debug foo} to create a
2232 stripped executable.
2233 @item Run @code{objcopy --add-gnu-debuglink=foo.dbg foo}
2234 to add a link to the debugging info into the stripped executable.
2235 @end enumerate
2236
2237 Note - the choice of @code{.dbg} as an extension for the debug info
2238 file is arbitrary. Also the @code{--only-keep-debug} step is
2239 optional. You could instead do this:
2240
2241 @enumerate
2242 @item Link the executable as normal.
2243 @item Copy @code{foo} to @code{foo.full}
2244 @item Run @code{strip --strip-debug foo}
2245 @item Run @code{objcopy --add-gnu-debuglink=foo.full foo}
2246 @end enumerate
2247
2248 ie the file pointed to by the @option{--add-gnu-debuglink} can be the
2249 full executable. It does not have to be a file created by the
2250 @option{--only-keep-debug} switch.
2251
2252 @item -V
2253 @itemx --version
2254 Show the version number for @command{strip}.
2255
2256 @item -v
2257 @itemx --verbose
2258 Verbose output: list all object files modified. In the case of
2259 archives, @samp{strip -v} lists all members of the archive.
2260 @end table
2261
2262 @c man end
2263
2264 @ignore
2265 @c man begin SEEALSO strip
2266 the Info entries for @file{binutils}.
2267 @c man end
2268 @end ignore
2269
2270 @node c++filt, addr2line, strip, Top
2271 @chapter c++filt
2272
2273 @kindex c++filt
2274 @cindex demangling C++ symbols
2275
2276 @c man title cxxfilt Demangle C++ and Java symbols.
2277
2278 @smallexample
2279 @c man begin SYNOPSIS cxxfilt
2280 c++filt [@option{-_}|@option{--strip-underscores}]
2281 [@option{-j}|@option{--java}]
2282 [@option{-n}|@option{--no-strip-underscores}]
2283 [@option{-s} @var{format}|@option{--format=}@var{format}]
2284 [@option{--help}] [@option{--version}] [@var{symbol}@dots{}]
2285 @c man end
2286 @end smallexample
2287
2288 @c man begin DESCRIPTION cxxfilt
2289
2290 @kindex cxxfilt
2291 The C++ and Java languages provides function overloading, which means
2292 that you can write many functions with the same name (providing each
2293 takes parameters of different types). All C++ and Java function names
2294 are encoded into a low-level assembly label (this process is known as
2295 @dfn{mangling}). The @command{c++filt}
2296 @footnote{MS-DOS does not allow @kbd{+} characters in file names, so on
2297 MS-DOS this program is named @command{cxxfilt}.}
2298 program does the inverse mapping: it decodes (@dfn{demangles}) low-level
2299 names into user-level names so that the linker can keep these overloaded
2300 functions from clashing.
2301
2302 Every alphanumeric word (consisting of letters, digits, underscores,
2303 dollars, or periods) seen in the input is a potential label. If the
2304 label decodes into a C++ name, the C++ name replaces the low-level
2305 name in the output.
2306
2307 You can use @command{c++filt} to decipher individual symbols:
2308
2309 @example
2310 c++filt @var{symbol}
2311 @end example
2312
2313 If no @var{symbol} arguments are given, @command{c++filt} reads symbol
2314 names from the standard input and writes the demangled names to the
2315 standard output. All results are printed on the standard output.
2316
2317 @c man end
2318
2319 @c man begin OPTIONS cxxfilt
2320
2321 @table @env
2322 @item -_
2323 @itemx --strip-underscores
2324 On some systems, both the C and C++ compilers put an underscore in front
2325 of every name. For example, the C name @code{foo} gets the low-level
2326 name @code{_foo}. This option removes the initial underscore. Whether
2327 @command{c++filt} removes the underscore by default is target dependent.
2328
2329 @item -j
2330 @itemx --java
2331 Prints demangled names using Java syntax. The default is to use C++
2332 syntax.
2333
2334 @item -n
2335 @itemx --no-strip-underscores
2336 Do not remove the initial underscore.
2337
2338 @item -s @var{format}
2339 @itemx --format=@var{format}
2340 @command{c++filt} can decode various methods of mangling, used by
2341 different compilers. The argument to this option selects which
2342 method it uses:
2343
2344 @table @code
2345 @item auto
2346 Automatic selection based on executable (the default method)
2347 @item gnu
2348 the one used by the @sc{gnu} C++ compiler (g++)
2349 @item lucid
2350 the one used by the Lucid compiler (lcc)
2351 @item arm
2352 the one specified by the C++ Annotated Reference Manual
2353 @item hp
2354 the one used by the HP compiler (aCC)
2355 @item edg
2356 the one used by the EDG compiler
2357 @item gnu-v3
2358 the one used by the @sc{gnu} C++ compiler (g++) with the V3 ABI.
2359 @item java
2360 the one used by the @sc{gnu} Java compiler (gcj)
2361 @item gnat
2362 the one used by the @sc{gnu} Ada compiler (GNAT).
2363 @end table
2364
2365 @item --help
2366 Print a summary of the options to @command{c++filt} and exit.
2367
2368 @item --version
2369 Print the version number of @command{c++filt} and exit.
2370 @end table
2371
2372 @c man end
2373
2374 @ignore
2375 @c man begin SEEALSO cxxfilt
2376 the Info entries for @file{binutils}.
2377 @c man end
2378 @end ignore
2379
2380 @quotation
2381 @emph{Warning:} @command{c++filt} is a new utility, and the details of its
2382 user interface are subject to change in future releases. In particular,
2383 a command-line option may be required in the the future to decode a name
2384 passed as an argument on the command line; in other words,
2385
2386 @example
2387 c++filt @var{symbol}
2388 @end example
2389
2390 @noindent
2391 may in a future release become
2392
2393 @example
2394 c++filt @var{option} @var{symbol}
2395 @end example
2396 @end quotation
2397
2398 @node addr2line
2399 @chapter addr2line
2400
2401 @kindex addr2line
2402 @cindex address to file name and line number
2403
2404 @c man title addr2line convert addresses into file names and line numbers.
2405
2406 @smallexample
2407 @c man begin SYNOPSIS addr2line
2408 addr2line [@option{-b} @var{bfdname}|@option{--target=}@var{bfdname}]
2409 [@option{-C}|@option{--demangle}[=@var{style}]]
2410 [@option{-e} @var{filename}|@option{--exe=}@var{filename}]
2411 [@option{-f}|@option{--functions}] [@option{-s}|@option{--basename}]
2412 [@option{-H}|@option{--help}] [@option{-V}|@option{--version}]
2413 [addr addr @dots{}]
2414 @c man end
2415 @end smallexample
2416
2417 @c man begin DESCRIPTION addr2line
2418
2419 @command{addr2line} translates program addresses into file names and line
2420 numbers. Given an address and an executable, it uses the debugging
2421 information in the executable to figure out which file name and line
2422 number are associated with a given address.
2423
2424 The executable to use is specified with the @option{-e} option. The
2425 default is the file @file{a.out}.
2426
2427 @command{addr2line} has two modes of operation.
2428
2429 In the first, hexadecimal addresses are specified on the command line,
2430 and @command{addr2line} displays the file name and line number for each
2431 address.
2432
2433 In the second, @command{addr2line} reads hexadecimal addresses from
2434 standard input, and prints the file name and line number for each
2435 address on standard output. In this mode, @command{addr2line} may be used
2436 in a pipe to convert dynamically chosen addresses.
2437
2438 The format of the output is @samp{FILENAME:LINENO}. The file name and
2439 line number for each address is printed on a separate line. If the
2440 @command{-f} option is used, then each @samp{FILENAME:LINENO} line is
2441 preceded by a @samp{FUNCTIONNAME} line which is the name of the function
2442 containing the address.
2443
2444 If the file name or function name can not be determined,
2445 @command{addr2line} will print two question marks in their place. If the
2446 line number can not be determined, @command{addr2line} will print 0.
2447
2448 @c man end
2449
2450 @c man begin OPTIONS addr2line
2451
2452 The long and short forms of options, shown here as alternatives, are
2453 equivalent.
2454
2455 @table @env
2456 @item -b @var{bfdname}
2457 @itemx --target=@var{bfdname}
2458 @cindex object code format
2459 Specify that the object-code format for the object files is
2460 @var{bfdname}.
2461
2462 @item -C
2463 @itemx --demangle[=@var{style}]
2464 @cindex demangling in objdump
2465 Decode (@dfn{demangle}) low-level symbol names into user-level names.
2466 Besides removing any initial underscore prepended by the system, this
2467 makes C++ function names readable. Different compilers have different
2468 mangling styles. The optional demangling style argument can be used to
2469 choose an appropriate demangling style for your compiler. @xref{c++filt},
2470 for more information on demangling.
2471
2472 @item -e @var{filename}
2473 @itemx --exe=@var{filename}
2474 Specify the name of the executable for which addresses should be
2475 translated. The default file is @file{a.out}.
2476
2477 @item -f
2478 @itemx --functions
2479 Display function names as well as file and line number information.
2480
2481 @item -s
2482 @itemx --basenames
2483 Display only the base of each file name.
2484 @end table
2485
2486 @c man end
2487
2488 @ignore
2489 @c man begin SEEALSO addr2line
2490 Info entries for @file{binutils}.
2491 @c man end
2492 @end ignore
2493
2494 @node nlmconv
2495 @chapter nlmconv
2496
2497 @command{nlmconv} converts a relocatable object file into a NetWare
2498 Loadable Module.
2499
2500 @ignore
2501 @command{nlmconv} currently works with @samp{i386} object
2502 files in @code{coff}, @sc{elf}, or @code{a.out} format, and @sc{SPARC}
2503 object files in @sc{elf}, or @code{a.out} format@footnote{
2504 @command{nlmconv} should work with any @samp{i386} or @sc{sparc} object
2505 format in the Binary File Descriptor library. It has only been tested
2506 with the above formats.}.
2507 @end ignore
2508
2509 @quotation
2510 @emph{Warning:} @command{nlmconv} is not always built as part of the binary
2511 utilities, since it is only useful for NLM targets.
2512 @end quotation
2513
2514 @c man title nlmconv converts object code into an NLM.
2515
2516 @smallexample
2517 @c man begin SYNOPSIS nlmconv
2518 nlmconv [@option{-I} @var{bfdname}|@option{--input-target=}@var{bfdname}]
2519 [@option{-O} @var{bfdname}|@option{--output-target=}@var{bfdname}]
2520 [@option{-T} @var{headerfile}|@option{--header-file=}@var{headerfile}]
2521 [@option{-d}|@option{--debug}] [@option{-l} @var{linker}|@option{--linker=}@var{linker}]
2522 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2523 @var{infile} @var{outfile}
2524 @c man end
2525 @end smallexample
2526
2527 @c man begin DESCRIPTION nlmconv
2528
2529 @command{nlmconv} converts the relocatable @samp{i386} object file
2530 @var{infile} into the NetWare Loadable Module @var{outfile}, optionally
2531 reading @var{headerfile} for NLM header information. For instructions
2532 on writing the NLM command file language used in header files, see the
2533 @samp{linkers} section, @samp{NLMLINK} in particular, of the @cite{NLM
2534 Development and Tools Overview}, which is part of the NLM Software
2535 Developer's Kit (``NLM SDK''), available from Novell, Inc.
2536 @command{nlmconv} uses the @sc{gnu} Binary File Descriptor library to read
2537 @var{infile};
2538 @ifclear man
2539 see @ref{BFD,,BFD,ld.info,Using LD}, for more information.
2540 @end ifclear
2541
2542 @command{nlmconv} can perform a link step. In other words, you can list
2543 more than one object file for input if you list them in the definitions
2544 file (rather than simply specifying one input file on the command line).
2545 In this case, @command{nlmconv} calls the linker for you.
2546
2547 @c man end
2548
2549 @c man begin OPTIONS nlmconv
2550
2551 @table @env
2552 @item -I @var{bfdname}
2553 @itemx --input-target=@var{bfdname}
2554 Object format of the input file. @command{nlmconv} can usually determine
2555 the format of a given file (so no default is necessary).
2556 @xref{Target Selection}, for more information.
2557
2558 @item -O @var{bfdname}
2559 @itemx --output-target=@var{bfdname}
2560 Object format of the output file. @command{nlmconv} infers the output
2561 format based on the input format, e.g. for a @samp{i386} input file the
2562 output format is @samp{nlm32-i386}.
2563 @xref{Target Selection}, for more information.
2564
2565 @item -T @var{headerfile}
2566 @itemx --header-file=@var{headerfile}
2567 Reads @var{headerfile} for NLM header information. For instructions on
2568 writing the NLM command file language used in header files, see@ see the
2569 @samp{linkers} section, of the @cite{NLM Development and Tools
2570 Overview}, which is part of the NLM Software Developer's Kit, available
2571 from Novell, Inc.
2572
2573 @item -d
2574 @itemx --debug
2575 Displays (on standard error) the linker command line used by @command{nlmconv}.
2576
2577 @item -l @var{linker}
2578 @itemx --linker=@var{linker}
2579 Use @var{linker} for any linking. @var{linker} can be an absolute or a
2580 relative pathname.
2581
2582 @item -h
2583 @itemx --help
2584 Prints a usage summary.
2585
2586 @item -V
2587 @itemx --version
2588 Prints the version number for @command{nlmconv}.
2589 @end table
2590
2591 @c man end
2592
2593 @ignore
2594 @c man begin SEEALSO nlmconv
2595 the Info entries for @file{binutils}.
2596 @c man end
2597 @end ignore
2598
2599 @node windres
2600 @chapter windres
2601
2602 @command{windres} may be used to manipulate Windows resources.
2603
2604 @quotation
2605 @emph{Warning:} @command{windres} is not always built as part of the binary
2606 utilities, since it is only useful for Windows targets.
2607 @end quotation
2608
2609 @c man title windres manipulate Windows resources.
2610
2611 @smallexample
2612 @c man begin SYNOPSIS windres
2613 windres [options] [input-file] [output-file]
2614 @c man end
2615 @end smallexample
2616
2617 @c man begin DESCRIPTION windres
2618
2619 @command{windres} reads resources from an input file and copies them into
2620 an output file. Either file may be in one of three formats:
2621
2622 @table @code
2623 @item rc
2624 A text format read by the Resource Compiler.
2625
2626 @item res
2627 A binary format generated by the Resource Compiler.
2628
2629 @item coff
2630 A COFF object or executable.
2631 @end table
2632
2633 The exact description of these different formats is available in
2634 documentation from Microsoft.
2635
2636 When @command{windres} converts from the @code{rc} format to the @code{res}
2637 format, it is acting like the Windows Resource Compiler. When
2638 @command{windres} converts from the @code{res} format to the @code{coff}
2639 format, it is acting like the Windows @code{CVTRES} program.
2640
2641 When @command{windres} generates an @code{rc} file, the output is similar
2642 but not identical to the format expected for the input. When an input
2643 @code{rc} file refers to an external filename, an output @code{rc} file
2644 will instead include the file contents.
2645
2646 If the input or output format is not specified, @command{windres} will
2647 guess based on the file name, or, for the input file, the file contents.
2648 A file with an extension of @file{.rc} will be treated as an @code{rc}
2649 file, a file with an extension of @file{.res} will be treated as a
2650 @code{res} file, and a file with an extension of @file{.o} or
2651 @file{.exe} will be treated as a @code{coff} file.
2652
2653 If no output file is specified, @command{windres} will print the resources
2654 in @code{rc} format to standard output.
2655
2656 The normal use is for you to write an @code{rc} file, use @command{windres}
2657 to convert it to a COFF object file, and then link the COFF file into
2658 your application. This will make the resources described in the
2659 @code{rc} file available to Windows.
2660
2661 @c man end
2662
2663 @c man begin OPTIONS windres
2664
2665 @table @env
2666 @item -i @var{filename}
2667 @itemx --input @var{filename}
2668 The name of the input file. If this option is not used, then
2669 @command{windres} will use the first non-option argument as the input file
2670 name. If there are no non-option arguments, then @command{windres} will
2671 read from standard input. @command{windres} can not read a COFF file from
2672 standard input.
2673
2674 @item -o @var{filename}
2675 @itemx --output @var{filename}
2676 The name of the output file. If this option is not used, then
2677 @command{windres} will use the first non-option argument, after any used
2678 for the input file name, as the output file name. If there is no
2679 non-option argument, then @command{windres} will write to standard output.
2680 @command{windres} can not write a COFF file to standard output. Note,
2681 for compatability with @command{rc} the option @option{-fo} is also
2682 accepted, but its use is not recommended.
2683
2684 @item -J @var{format}
2685 @itemx --input-format @var{format}
2686 The input format to read. @var{format} may be @samp{res}, @samp{rc}, or
2687 @samp{coff}. If no input format is specified, @command{windres} will
2688 guess, as described above.
2689
2690 @item -O @var{format}
2691 @itemx --output-format @var{format}
2692 The output format to generate. @var{format} may be @samp{res},
2693 @samp{rc}, or @samp{coff}. If no output format is specified,
2694 @command{windres} will guess, as described above.
2695
2696 @item -F @var{target}
2697 @itemx --target @var{target}
2698 Specify the BFD format to use for a COFF file as input or output. This
2699 is a BFD target name; you can use the @option{--help} option to see a list
2700 of supported targets. Normally @command{windres} will use the default
2701 format, which is the first one listed by the @option{--help} option.
2702 @ifclear man
2703 @ref{Target Selection}.
2704 @end ifclear
2705
2706 @item --preprocessor @var{program}
2707 When @command{windres} reads an @code{rc} file, it runs it through the C
2708 preprocessor first. This option may be used to specify the preprocessor
2709 to use, including any leading arguments. The default preprocessor
2710 argument is @code{gcc -E -xc-header -DRC_INVOKED}.
2711
2712 @item -I @var{directory}
2713 @itemx --include-dir @var{directory}
2714 Specify an include directory to use when reading an @code{rc} file.
2715 @command{windres} will pass this to the preprocessor as an @option{-I}
2716 option. @command{windres} will also search this directory when looking for
2717 files named in the @code{rc} file. If the argument passed to this command
2718 matches any of the supported @var{formats} (as descrived in the @option{-J}
2719 option), it will issue a deprecation warning, and behave just like the
2720 @option{-J} option. New programs should not use this behaviour. If a
2721 directory happens to match a @var{format}, simple prefix it with @samp{./}
2722 to disable the backward compatibility.
2723
2724 @item -D @var{target}
2725 @itemx --define @var{sym}[=@var{val}]
2726 Specify a @option{-D} option to pass to the preprocessor when reading an
2727 @code{rc} file.
2728
2729 @item -U @var{target}
2730 @itemx --undefine @var{sym}
2731 Specify a @option{-U} option to pass to the preprocessor when reading an
2732 @code{rc} file.
2733
2734 @item -r
2735 Ignored for compatibility with rc.
2736
2737 @item -v
2738 Enable verbose mode. This tells you what the preprocessor is if you
2739 didn't specify one.
2740
2741 @item -l @var{val}
2742 @item --language @var{val}
2743 Specify the default language to use when reading an @code{rc} file.
2744 @var{val} should be a hexadecimal language code. The low eight bits are
2745 the language, and the high eight bits are the sublanguage.
2746
2747 @item --use-temp-file
2748 Use a temporary file to instead of using popen to read the output of
2749 the preprocessor. Use this option if the popen implementation is buggy
2750 on the host (eg., certain non-English language versions of Windows 95 and
2751 Windows 98 are known to have buggy popen where the output will instead
2752 go the console).
2753
2754 @item --no-use-temp-file
2755 Use popen, not a temporary file, to read the output of the preprocessor.
2756 This is the default behaviour.
2757
2758 @item -h
2759 @item --help
2760 Prints a usage summary.
2761
2762 @item -V
2763 @item --version
2764 Prints the version number for @command{windres}.
2765
2766 @item --yydebug
2767 If @command{windres} is compiled with @code{YYDEBUG} defined as @code{1},
2768 this will turn on parser debugging.
2769 @end table
2770
2771 @c man end
2772
2773 @ignore
2774 @c man begin SEEALSO windres
2775 the Info entries for @file{binutils}.
2776 @c man end
2777 @end ignore
2778
2779 @node dlltool
2780 @chapter Create files needed to build and use DLLs
2781 @cindex DLL
2782 @kindex dlltool
2783
2784 @command{dlltool} may be used to create the files needed to build and use
2785 dynamic link libraries (DLLs).
2786
2787 @quotation
2788 @emph{Warning:} @command{dlltool} is not always built as part of the binary
2789 utilities, since it is only useful for those targets which support DLLs.
2790 @end quotation
2791
2792 @c man title dlltool Create files needed to build and use DLLs.
2793
2794 @smallexample
2795 @c man begin SYNOPSIS dlltool
2796 dlltool [@option{-d}|@option{--input-def} @var{def-file-name}]
2797 [@option{-b}|@option{--base-file} @var{base-file-name}]
2798 [@option{-e}|@option{--output-exp} @var{exports-file-name}]
2799 [@option{-z}|@option{--output-def} @var{def-file-name}]
2800 [@option{-l}|@option{--output-lib} @var{library-file-name}]
2801 [@option{--export-all-symbols}] [@option{--no-export-all-symbols}]
2802 [@option{--exclude-symbols} @var{list}]
2803 [@option{--no-default-excludes}]
2804 [@option{-S}|@option{--as} @var{path-to-assembler}] [@option{-f}|@option{--as-flags} @var{options}]
2805 [@option{-D}|@option{--dllname} @var{name}] [@option{-m}|@option{--machine} @var{machine}]
2806 [@option{-a}|@option{--add-indirect}] [@option{-U}|@option{--add-underscore}] [@option{-k}|@option{--kill-at}]
2807 [@option{-A}|@option{--add-stdcall-alias}]
2808 [@option{-x}|@option{--no-idata4}] [@option{-c}|@option{--no-idata5}] [@option{-i}|@option{--interwork}]
2809 [@option{-n}|@option{--nodelete}] [@option{-v}|@option{--verbose}]
2810 [@option{-h}|@option{--help}] [@option{-V}|@option{--version}]
2811 [object-file @dots{}]
2812 @c man end
2813 @end smallexample
2814
2815 @c man begin DESCRIPTION dlltool
2816
2817 @command{dlltool} reads its inputs, which can come from the @option{-d} and
2818 @option{-b} options as well as object files specified on the command
2819 line. It then processes these inputs and if the @option{-e} option has
2820 been specified it creates a exports file. If the @option{-l} option
2821 has been specified it creates a library file and if the @option{-z} option
2822 has been specified it creates a def file. Any or all of the @option{-e},
2823 @option{-l} and @option{-z} options can be present in one invocation of
2824 dlltool.
2825
2826 When creating a DLL, along with the source for the DLL, it is necessary
2827 to have three other files. @command{dlltool} can help with the creation of
2828 these files.
2829
2830 The first file is a @samp{.def} file which specifies which functions are
2831 exported from the DLL, which functions the DLL imports, and so on. This
2832 is a text file and can be created by hand, or @command{dlltool} can be used
2833 to create it using the @option{-z} option. In this case @command{dlltool}
2834 will scan the object files specified on its command line looking for
2835 those functions which have been specially marked as being exported and
2836 put entries for them in the .def file it creates.
2837
2838 In order to mark a function as being exported from a DLL, it needs to
2839 have an @option{-export:<name_of_function>} entry in the @samp{.drectve}
2840 section of the object file. This can be done in C by using the
2841 asm() operator:
2842
2843 @smallexample
2844 asm (".section .drectve");
2845 asm (".ascii \"-export:my_func\"");
2846
2847 int my_func (void) @{ @dots{} @}
2848 @end smallexample
2849
2850 The second file needed for DLL creation is an exports file. This file
2851 is linked with the object files that make up the body of the DLL and it
2852 handles the interface between the DLL and the outside world. This is a
2853 binary file and it can be created by giving the @option{-e} option to
2854 @command{dlltool} when it is creating or reading in a .def file.
2855
2856 The third file needed for DLL creation is the library file that programs
2857 will link with in order to access the functions in the DLL. This file
2858 can be created by giving the @option{-l} option to dlltool when it
2859 is creating or reading in a .def file.
2860
2861 @command{dlltool} builds the library file by hand, but it builds the
2862 exports file by creating temporary files containing assembler statements
2863 and then assembling these. The @option{-S} command line option can be
2864 used to specify the path to the assembler that dlltool will use,
2865 and the @option{-f} option can be used to pass specific flags to that
2866 assembler. The @option{-n} can be used to prevent dlltool from deleting
2867 these temporary assembler files when it is done, and if @option{-n} is
2868 specified twice then this will prevent dlltool from deleting the
2869 temporary object files it used to build the library.
2870
2871 Here is an example of creating a DLL from a source file @samp{dll.c} and
2872 also creating a program (from an object file called @samp{program.o})
2873 that uses that DLL:
2874
2875 @smallexample
2876 gcc -c dll.c
2877 dlltool -e exports.o -l dll.lib dll.o
2878 gcc dll.o exports.o -o dll.dll
2879 gcc program.o dll.lib -o program
2880 @end smallexample
2881
2882 @c man end
2883
2884 @c man begin OPTIONS dlltool
2885
2886 The command line options have the following meanings:
2887
2888 @table @env
2889
2890 @item -d @var{filename}
2891 @itemx --input-def @var{filename}
2892 @cindex input .def file
2893 Specifies the name of a .def file to be read in and processed.
2894
2895 @item -b @var{filename}
2896 @itemx --base-file @var{filename}
2897 @cindex base files
2898 Specifies the name of a base file to be read in and processed. The
2899 contents of this file will be added to the relocation section in the
2900 exports file generated by dlltool.
2901
2902 @item -e @var{filename}
2903 @itemx --output-exp @var{filename}
2904 Specifies the name of the export file to be created by dlltool.
2905
2906 @item -z @var{filename}
2907 @itemx --output-def @var{filename}
2908 Specifies the name of the .def file to be created by dlltool.
2909
2910 @item -l @var{filename}
2911 @itemx --output-lib @var{filename}
2912 Specifies the name of the library file to be created by dlltool.
2913
2914 @item --export-all-symbols
2915 Treat all global and weak defined symbols found in the input object
2916 files as symbols to be exported. There is a small list of symbols which
2917 are not exported by default; see the @option{--no-default-excludes}
2918 option. You may add to the list of symbols to not export by using the
2919 @option{--exclude-symbols} option.
2920
2921 @item --no-export-all-symbols
2922 Only export symbols explicitly listed in an input .def file or in
2923 @samp{.drectve} sections in the input object files. This is the default
2924 behaviour. The @samp{.drectve} sections are created by @samp{dllexport}
2925 attributes in the source code.
2926
2927 @item --exclude-symbols @var{list}
2928 Do not export the symbols in @var{list}. This is a list of symbol names
2929 separated by comma or colon characters. The symbol names should not
2930 contain a leading underscore. This is only meaningful when
2931 @option{--export-all-symbols} is used.
2932
2933 @item --no-default-excludes
2934 When @option{--export-all-symbols} is used, it will by default avoid
2935 exporting certain special symbols. The current list of symbols to avoid
2936 exporting is @samp{DllMain@@12}, @samp{DllEntryPoint@@0},
2937 @samp{impure_ptr}. You may use the @option{--no-default-excludes} option
2938 to go ahead and export these special symbols. This is only meaningful
2939 when @option{--export-all-symbols} is used.
2940
2941 @item -S @var{path}
2942 @itemx --as @var{path}
2943 Specifies the path, including the filename, of the assembler to be used
2944 to create the exports file.
2945
2946 @item -f @var{options}
2947 @itemx --as-flags @var{options}
2948 Specifies any specific command line options to be passed to the
2949 assembler when building the exports file. This option will work even if
2950 the @option{-S} option is not used. This option only takes one argument,
2951 and if it occurs more than once on the command line, then later
2952 occurrences will override earlier occurrences. So if it is necessary to
2953 pass multiple options to the assembler they should be enclosed in
2954 double quotes.
2955
2956 @item -D @var{name}
2957 @itemx --dll-name @var{name}
2958 Specifies the name to be stored in the .def file as the name of the DLL
2959 when the @option{-e} option is used. If this option is not present, then
2960 the filename given to the @option{-e} option will be used as the name of
2961 the DLL.
2962
2963 @item -m @var{machine}
2964 @itemx -machine @var{machine}
2965 Specifies the type of machine for which the library file should be
2966 built. @command{dlltool} has a built in default type, depending upon how
2967 it was created, but this option can be used to override that. This is
2968 normally only useful when creating DLLs for an ARM processor, when the
2969 contents of the DLL are actually encode using Thumb instructions.
2970
2971 @item -a
2972 @itemx --add-indirect
2973 Specifies that when @command{dlltool} is creating the exports file it
2974 should add a section which allows the exported functions to be
2975 referenced without using the import library. Whatever the hell that
2976 means!
2977
2978 @item -U
2979 @itemx --add-underscore
2980 Specifies that when @command{dlltool} is creating the exports file it
2981 should prepend an underscore to the names of the exported functions.
2982
2983 @item -k
2984 @itemx --kill-at
2985 Specifies that when @command{dlltool} is creating the exports file it
2986 should not append the string @samp{@@ <number>}. These numbers are
2987 called ordinal numbers and they represent another way of accessing the
2988 function in a DLL, other than by name.
2989
2990 @item -A
2991 @itemx --add-stdcall-alias
2992 Specifies that when @command{dlltool} is creating the exports file it
2993 should add aliases for stdcall symbols without @samp{@@ <number>}
2994 in addition to the symbols with @samp{@@ <number>}.
2995
2996 @item -x
2997 @itemx --no-idata4
2998 Specifies that when @command{dlltool} is creating the exports and library
2999 files it should omit the @code{.idata4} section. This is for compatibility
3000 with certain operating systems.
3001
3002 @item -c
3003 @itemx --no-idata5
3004 Specifies that when @command{dlltool} is creating the exports and library
3005 files it should omit the @code{.idata5} section. This is for compatibility
3006 with certain operating systems.
3007
3008 @item -i
3009 @itemx --interwork
3010 Specifies that @command{dlltool} should mark the objects in the library
3011 file and exports file that it produces as supporting interworking
3012 between ARM and Thumb code.
3013
3014 @item -n
3015 @itemx --nodelete
3016 Makes @command{dlltool} preserve the temporary assembler files it used to
3017 create the exports file. If this option is repeated then dlltool will
3018 also preserve the temporary object files it uses to create the library
3019 file.
3020
3021 @item -v
3022 @itemx --verbose
3023 Make dlltool describe what it is doing.
3024
3025 @item -h
3026 @itemx --help
3027 Displays a list of command line options and then exits.
3028
3029 @item -V
3030 @itemx --version
3031 Displays dlltool's version number and then exits.
3032
3033 @end table
3034
3035 @c man end
3036
3037 @ignore
3038 @c man begin SEEALSO dlltool
3039 the Info entries for @file{binutils}.
3040 @c man end
3041 @end ignore
3042
3043 @node readelf
3044 @chapter readelf
3045
3046 @cindex ELF file information
3047 @kindex readelf
3048
3049 @c man title readelf Displays information about ELF files.
3050
3051 @smallexample
3052 @c man begin SYNOPSIS readelf
3053 readelf [@option{-a}|@option{--all}]
3054 [@option{-h}|@option{--file-header}]
3055 [@option{-l}|@option{--program-headers}|@option{--segments}]
3056 [@option{-S}|@option{--section-headers}|@option{--sections}]
3057 [@option{-e}|@option{--headers}]
3058 [@option{-s}|@option{--syms}|@option{--symbols}]
3059 [@option{-n}|@option{--notes}]
3060 [@option{-r}|@option{--relocs}]
3061 [@option{-u}|@option{--unwind}]
3062 [@option{-d}|@option{--dynamic}]
3063 [@option{-V}|@option{--version-info}]
3064 [@option{-A}|@option{--arch-specific}]
3065 [@option{-D}|@option{--use-dynamic}]
3066 [@option{-x} <number>|@option{--hex-dump=}<number>]
3067 [@option{-w[liaprmfFso]}|
3068 @option{--debug-dump}[=line,=info,=abbrev,=pubnames,=ranges,=macro,=frames,=frames-interp,=str,=loc]]
3069 [@option{-I}|@option{-histogram}]
3070 [@option{-v}|@option{--version}]
3071 [@option{-W}|@option{--wide}]
3072 [@option{-H}|@option{--help}]
3073 @var{elffile}@dots{}
3074 @c man end
3075 @end smallexample
3076
3077 @c man begin DESCRIPTION readelf
3078
3079 @command{readelf} displays information about one or more ELF format object
3080 files. The options control what particular information to display.
3081
3082 @var{elffile}@dots{} are the object files to be examined. 32-bit and
3083 64-bit ELF files are supported, as are archives containing ELF files.
3084
3085 @c man end
3086
3087 @c man begin OPTIONS readelf
3088
3089 The long and short forms of options, shown here as alternatives, are
3090 equivalent. At least one option besides @samp{-v} or @samp{-H} must be
3091 given.
3092
3093 @table @env
3094 @item -a
3095 @itemx --all
3096 Equivalent to specifiying @option{--file-header},
3097 @option{--program-headers}, @option{--sections}, @option{--symbols},
3098 @option{--relocs}, @option{--dynamic}, @option{--notes} and
3099 @option{--version-info}.
3100
3101 @item -h
3102 @itemx --file-header
3103 @cindex ELF file header information
3104 Displays the information contained in the ELF header at the start of the
3105 file.
3106
3107 @item -l
3108 @itemx --program-headers
3109 @itemx --segments
3110 @cindex ELF program header information
3111 @cindex ELF segment information
3112 Displays the information contained in the file's segment headers, if it
3113 has any.
3114
3115 @item -S
3116 @itemx --sections
3117 @itemx --section-headers
3118 @cindex ELF section information
3119 Displays the information contained in the file's section headers, if it
3120 has any.
3121
3122 @item -s
3123 @itemx --symbols
3124 @itemx --syms
3125 @cindex ELF symbol table information
3126 Displays the entries in symbol table section of the file, if it has one.
3127
3128 @item -e
3129 @itemx --headers
3130 Display all the headers in the file. Equivalent to @option{-h -l -S}.
3131
3132 @item -n
3133 @itemx --notes
3134 @cindex ELF core notes
3135 Displays the contents of the NOTE segment, if it exists.
3136
3137 @item -r
3138 @itemx --relocs
3139 @cindex ELF reloc information
3140 Displays the contents of the file's relocation section, if it has one.
3141
3142 @item -u
3143 @itemx --unwind
3144 @cindex unwind information
3145 Displays the contents of the file's unwind section, if it has one. Only
3146 the unwind sections for IA64 ELF files are currently supported.
3147
3148 @item -u
3149 @itemx --unwind
3150 @cindex unwind information
3151 Displays the contents of the file's unwind section, if it has one. Only
3152 the unwind sections for IA64 ELF files are currently supported.
3153
3154 @item -d
3155 @itemx --dynamic
3156 @cindex ELF dynamic section information
3157 Displays the contents of the file's dynamic section, if it has one.
3158
3159 @item -V
3160 @itemx --version-info
3161 @cindex ELF version sections informations
3162 Displays the contents of the version sections in the file, it they
3163 exist.
3164
3165 @item -A
3166 @itemx --arch-specific
3167 Displays architecture-specific information in the file, if there
3168 is any.
3169
3170 @item -D
3171 @itemx --use-dynamic
3172 When displaying symbols, this option makes @command{readelf} use the
3173 symbol table in the file's dynamic section, rather than the one in the
3174 symbols section.
3175
3176 @item -x <number>
3177 @itemx --hex-dump=<number>
3178 Displays the contents of the indicated section as a hexadecimal dump.
3179
3180 @item -w[liaprmfFso]
3181 @itemx --debug-dump[=line,=info,=abbrev,=pubnames,=ranges,=macro,=frames,=frames-interp,=str,=loc]
3182 Displays the contents of the debug sections in the file, if any are
3183 present. If one of the optional letters or words follows the switch
3184 then only data found in those specific sections will be dumped.
3185
3186 @item -I
3187 @itemx --histogram
3188 Display a histogram of bucket list lengths when displaying the contents
3189 of the symbol tables.
3190
3191 @item -v
3192 @itemx --version
3193 Display the version number of readelf.
3194
3195 @item -W
3196 @itemx --wide
3197 Don't break output lines to fit into 80 columns. By default
3198 @command{readelf} breaks section header and segment listing lines for
3199 64-bit ELF files, so that they fit into 80 columns. This option causes
3200 @command{readelf} to print each section header resp. each segment one a
3201 single line, which is far more readable on terminals wider than 80 columns.
3202
3203 @item -H
3204 @itemx --help
3205 Display the command line options understood by @command{readelf}.
3206
3207 @end table
3208
3209 @c man end
3210
3211 @ignore
3212 @c man begin SEEALSO readelf
3213 objdump(1), and the Info entries for @file{binutils}.
3214 @c man end
3215 @end ignore
3216
3217 @node Selecting The Target System
3218 @chapter Selecting the Target System
3219
3220 You can specify two aspects of the target system to the @sc{gnu}
3221 binary file utilities, each in several ways:
3222
3223 @itemize @bullet
3224 @item
3225 the target
3226
3227 @item
3228 the architecture
3229 @end itemize
3230
3231 In the following summaries, the lists of ways to specify values are in
3232 order of decreasing precedence. The ways listed first override those
3233 listed later.
3234
3235 The commands to list valid values only list the values for which the
3236 programs you are running were configured. If they were configured with
3237 @option{--enable-targets=all}, the commands list most of the available
3238 values, but a few are left out; not all targets can be configured in at
3239 once because some of them can only be configured @dfn{native} (on hosts
3240 with the same type as the target system).
3241
3242 @menu
3243 * Target Selection::
3244 * Architecture Selection::
3245 @end menu
3246
3247 @node Target Selection
3248 @section Target Selection
3249
3250 A @dfn{target} is an object file format. A given target may be
3251 supported for multiple architectures (@pxref{Architecture Selection}).
3252 A target selection may also have variations for different operating
3253 systems or architectures.
3254
3255 The command to list valid target values is @samp{objdump -i}
3256 (the first column of output contains the relevant information).
3257
3258 Some sample values are: @samp{a.out-hp300bsd}, @samp{ecoff-littlemips},
3259 @samp{a.out-sunos-big}.
3260
3261 You can also specify a target using a configuration triplet. This is
3262 the same sort of name that is passed to @file{configure} to specify a
3263 target. When you use a configuration triplet as an argument, it must be
3264 fully canonicalized. You can see the canonical version of a triplet by
3265 running the shell script @file{config.sub} which is included with the
3266 sources.
3267
3268 Some sample configuration triplets are: @samp{m68k-hp-bsd},
3269 @samp{mips-dec-ultrix}, @samp{sparc-sun-sunos}.
3270
3271 @subheading @command{objdump} Target
3272
3273 Ways to specify:
3274
3275 @enumerate
3276 @item
3277 command line option: @option{-b} or @option{--target}
3278
3279 @item
3280 environment variable @code{GNUTARGET}
3281
3282 @item
3283 deduced from the input file
3284 @end enumerate
3285
3286 @subheading @command{objcopy} and @command{strip} Input Target
3287
3288 Ways to specify:
3289
3290 @enumerate
3291 @item
3292 command line options: @option{-I} or @option{--input-target}, or @option{-F} or @option{--target}
3293
3294 @item
3295 environment variable @code{GNUTARGET}
3296
3297 @item
3298 deduced from the input file
3299 @end enumerate
3300
3301 @subheading @command{objcopy} and @command{strip} Output Target
3302
3303 Ways to specify:
3304
3305 @enumerate
3306 @item
3307 command line options: @option{-O} or @option{--output-target}, or @option{-F} or @option{--target}
3308
3309 @item
3310 the input target (see ``@command{objcopy} and @command{strip} Input Target'' above)
3311
3312 @item
3313 environment variable @code{GNUTARGET}
3314
3315 @item
3316 deduced from the input file
3317 @end enumerate
3318
3319 @subheading @command{nm}, @command{size}, and @command{strings} Target
3320
3321 Ways to specify:
3322
3323 @enumerate
3324 @item
3325 command line option: @option{--target}
3326
3327 @item
3328 environment variable @code{GNUTARGET}
3329
3330 @item
3331 deduced from the input file
3332 @end enumerate
3333
3334 @node Architecture Selection
3335 @section Architecture Selection
3336
3337 An @dfn{architecture} is a type of @sc{cpu} on which an object file is
3338 to run. Its name may contain a colon, separating the name of the
3339 processor family from the name of the particular @sc{cpu}.
3340
3341 The command to list valid architecture values is @samp{objdump -i} (the
3342 second column contains the relevant information).
3343
3344 Sample values: @samp{m68k:68020}, @samp{mips:3000}, @samp{sparc}.
3345
3346 @subheading @command{objdump} Architecture
3347
3348 Ways to specify:
3349
3350 @enumerate
3351 @item
3352 command line option: @option{-m} or @option{--architecture}
3353
3354 @item
3355 deduced from the input file
3356 @end enumerate
3357
3358 @subheading @command{objcopy}, @command{nm}, @command{size}, @command{strings} Architecture
3359
3360 Ways to specify:
3361
3362 @enumerate
3363 @item
3364 deduced from the input file
3365 @end enumerate
3366
3367 @node Reporting Bugs
3368 @chapter Reporting Bugs
3369 @cindex bugs
3370 @cindex reporting bugs
3371
3372 Your bug reports play an essential role in making the binary utilities
3373 reliable.
3374
3375 Reporting a bug may help you by bringing a solution to your problem, or
3376 it may not. But in any case the principal function of a bug report is
3377 to help the entire community by making the next version of the binary
3378 utilities work better. Bug reports are your contribution to their
3379 maintenance.
3380
3381 In order for a bug report to serve its purpose, you must include the
3382 information that enables us to fix the bug.
3383
3384 @menu
3385 * Bug Criteria:: Have you found a bug?
3386 * Bug Reporting:: How to report bugs
3387 @end menu
3388
3389 @node Bug Criteria
3390 @section Have You Found a Bug?
3391 @cindex bug criteria
3392
3393 If you are not sure whether you have found a bug, here are some guidelines:
3394
3395 @itemize @bullet
3396 @cindex fatal signal
3397 @cindex crash
3398 @item
3399 If a binary utility gets a fatal signal, for any input whatever, that is
3400 a bug. Reliable utilities never crash.
3401
3402 @cindex error on valid input
3403 @item
3404 If a binary utility produces an error message for valid input, that is a
3405 bug.
3406
3407 @item
3408 If you are an experienced user of binary utilities, your suggestions for
3409 improvement are welcome in any case.
3410 @end itemize
3411
3412 @node Bug Reporting
3413 @section How to Report Bugs
3414 @cindex bug reports
3415 @cindex bugs, reporting
3416
3417 A number of companies and individuals offer support for @sc{gnu}
3418 products. If you obtained the binary utilities from a support
3419 organization, we recommend you contact that organization first.
3420
3421 You can find contact information for many support companies and
3422 individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs
3423 distribution.
3424
3425 In any event, we also recommend that you send bug reports for the binary
3426 utilities to @samp{bug-binutils@@gnu.org}.
3427
3428 The fundamental principle of reporting bugs usefully is this:
3429 @strong{report all the facts}. If you are not sure whether to state a
3430 fact or leave it out, state it!
3431
3432 Often people omit facts because they think they know what causes the
3433 problem and assume that some details do not matter. Thus, you might
3434 assume that the name of a file you use in an example does not matter.
3435 Well, probably it does not, but one cannot be sure. Perhaps the bug is
3436 a stray memory reference which happens to fetch from the location where
3437 that pathname is stored in memory; perhaps, if the pathname were
3438 different, the contents of that location would fool the utility into
3439 doing the right thing despite the bug. Play it safe and give a
3440 specific, complete example. That is the easiest thing for you to do,
3441 and the most helpful.
3442
3443 Keep in mind that the purpose of a bug report is to enable us to fix the bug if
3444 it is new to us. Therefore, always write your bug reports on the assumption
3445 that the bug has not been reported previously.
3446
3447 Sometimes people give a few sketchy facts and ask, ``Does this ring a
3448 bell?'' This cannot help us fix a bug, so it is basically useless. We
3449 respond by asking for enough details to enable us to investigate.
3450 You might as well expedite matters by sending them to begin with.
3451
3452 To enable us to fix the bug, you should include all these things:
3453
3454 @itemize @bullet
3455 @item
3456 The version of the utility. Each utility announces it if you start it
3457 with the @option{--version} argument.
3458
3459 Without this, we will not know whether there is any point in looking for
3460 the bug in the current version of the binary utilities.
3461
3462 @item
3463 Any patches you may have applied to the source, including any patches
3464 made to the @code{BFD} library.
3465
3466 @item
3467 The type of machine you are using, and the operating system name and
3468 version number.
3469
3470 @item
3471 What compiler (and its version) was used to compile the utilities---e.g.
3472 ``@code{gcc-2.7}''.
3473
3474 @item
3475 The command arguments you gave the utility to observe the bug. To
3476 guarantee you will not omit something important, list them all. A copy
3477 of the Makefile (or the output from make) is sufficient.
3478
3479 If we were to try to guess the arguments, we would probably guess wrong
3480 and then we might not encounter the bug.
3481
3482 @item
3483 A complete input file, or set of input files, that will reproduce the
3484 bug. If the utility is reading an object file or files, then it is
3485 generally most helpful to send the actual object files, uuencoded if
3486 necessary to get them through the mail system. Note that
3487 @samp{bug-binutils@@gnu.org} is a mailing list, so you should avoid
3488 sending very large files to it. Making the files available for
3489 anonymous FTP is OK.
3490
3491 If the source files were produced exclusively using @sc{gnu} programs
3492 (e.g., @command{gcc}, @command{gas}, and/or the @sc{gnu} @command{ld}), then it
3493 may be OK to send the source files rather than the object files. In
3494 this case, be sure to say exactly what version of @command{gcc}, or
3495 whatever, was used to produce the object files. Also say how
3496 @command{gcc}, or whatever, was configured.
3497
3498 @item
3499 A description of what behavior you observe that you believe is
3500 incorrect. For example, ``It gets a fatal signal.''
3501
3502 Of course, if the bug is that the utility gets a fatal signal, then we
3503 will certainly notice it. But if the bug is incorrect output, we might
3504 not notice unless it is glaringly wrong. You might as well not give us
3505 a chance to make a mistake.
3506
3507 Even if the problem you experience is a fatal signal, you should still
3508 say so explicitly. Suppose something strange is going on, such as your
3509 copy of the utility is out of synch, or you have encountered a bug in
3510 the C library on your system. (This has happened!) Your copy might
3511 crash and ours would not. If you told us to expect a crash, then when
3512 ours fails to crash, we would know that the bug was not happening for
3513 us. If you had not told us to expect a crash, then we would not be able
3514 to draw any conclusion from our observations.
3515
3516 @item
3517 If you wish to suggest changes to the source, send us context diffs, as
3518 generated by @command{diff} with the @option{-u}, @option{-c}, or @option{-p}
3519 option. Always send diffs from the old file to the new file. If you
3520 wish to discuss something in the @command{ld} source, refer to it by
3521 context, not by line number.
3522
3523 The line numbers in our development sources will not match those in your
3524 sources. Your line numbers would convey no useful information to us.
3525 @end itemize
3526
3527 Here are some things that are not necessary:
3528
3529 @itemize @bullet
3530 @item
3531 A description of the envelope of the bug.
3532
3533 Often people who encounter a bug spend a lot of time investigating
3534 which changes to the input file will make the bug go away and which
3535 changes will not affect it.
3536
3537 This is often time consuming and not very useful, because the way we
3538 will find the bug is by running a single example under the debugger
3539 with breakpoints, not by pure deduction from a series of examples.
3540 We recommend that you save your time for something else.
3541
3542 Of course, if you can find a simpler example to report @emph{instead}
3543 of the original one, that is a convenience for us. Errors in the
3544 output will be easier to spot, running under the debugger will take
3545 less time, and so on.
3546
3547 However, simplification is not vital; if you do not want to do this,
3548 report the bug anyway and send us the entire test case you used.
3549
3550 @item
3551 A patch for the bug.
3552
3553 A patch for the bug does help us if it is a good one. But do not omit
3554 the necessary information, such as the test case, on the assumption that
3555 a patch is all we need. We might see problems with your patch and decide
3556 to fix the problem another way, or we might not understand it at all.
3557
3558 Sometimes with programs as complicated as the binary utilities it is
3559 very hard to construct an example that will make the program follow a
3560 certain path through the code. If you do not send us the example, we
3561 will not be able to construct one, so we will not be able to verify that
3562 the bug is fixed.
3563
3564 And if we cannot understand what bug you are trying to fix, or why your
3565 patch should be an improvement, we will not install it. A test case will
3566 help us to understand.
3567
3568 @item
3569 A guess about what the bug is or what it depends on.
3570
3571 Such guesses are usually wrong. Even we cannot guess right about such
3572 things without first using the debugger to find the facts.
3573 @end itemize
3574
3575 @include fdl.texi
3576
3577 @node Index
3578 @unnumbered Index
3579
3580 @printindex cp
3581
3582 @contents
3583 @bye