From 29a2b7448cfacefb0f517abe838515cf007a3caf Mon Sep 17 00:00:00 2001 From: Roland Pesch Date: Sat, 7 Dec 1991 04:19:03 +0000 Subject: [PATCH] About 40% of changes sugg. by Bob Chassell --- gdb/doc/gdb.texinfo | 1052 +++++++++++++++++++++++-------------------- 1 file changed, 552 insertions(+), 500 deletions(-) diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo index 8c13f92b850..f16a010ffb6 100644 --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -1,18 +1,49 @@ _dnl__ -*-Texinfo-*- _dnl__ Copyright (c) 1988 1989 1990 1991 Free Software Foundation, Inc. -\input texinfo +_dnl__ $Id$ +\input texinfo @c -*-texinfo-*- +@c Copyright (c) 1988 1989 1990 1991 Free Software Foundation, Inc. +@c %**start of header @setfilename _GDBP__.info -@c $Id$ +_if__(_GENERIC__) +@settitle Using _GDBN__ (_GDB_VN__) +_fi__(_GENERIC__) +_if__(!_GENERIC__) +@settitle Using _GDBN__ _GDB_VN__ (_HOST__) +_fi__(!_GENERIC__) +@setchapternewpage odd +@c @smallbook +@c @cropmarks +@c %**end of header + +@finalout +@syncodeindex ky cp + +_0__@c ===> NOTE! <==_1__ +@c Determine the edition number in *three* places by hand: +@c 1. First ifinfo section 2. title page 3. top node +@c To find the locations, search for !!set + +@c The following is for Pesch for his RCS system. +@c This revision number *not* the same as the Edition number. +@tex +\def\$#1${{#1}} % Kluge: collect RCS revision info without $...$ +\xdef\manvers{\$Revision$} % For use in headers, footers too +@end tex + +@c FOR UPDATES LEADING TO THIS DRAFT, GDB CHANGELOG CONSULTED BETWEEN: +@c Fri Oct 11 23:27:06 1991 John Gilmore (gnu at cygnus.com) +@c Sat Dec 22 02:51:40 1990 John Gilmore (gnu at cygint) + @c THIS MANUAL REQUIRES TEXINFO-2 macros and info-makers to format properly. -@c + @ifinfo @format START-INFO-DIR-ENTRY -* Gdb: (gdb). The GNU debugger. +* Gdb: (gdb). The GNU debugger. END-INFO-DIR-ENTRY @end format @end ifinfo - _if__(0) NOTE: this manual is marked up for preprocessing with a collection @@ -22,27 +53,22 @@ THIS IS THE SOURCE PRIOR TO PREPROCESSING. The full source needs to be run through m4 before either tex- or info- formatting: for example, _0__ m4 pretex.m4 none.m4 all.m4 gdb.texinfo >gdb-all.texinfo -_1__ will produce (assuming your path finds either GNU m4 >= 0.84, or SysV m4; Berkeley won't do) a file suitable for formatting. See the text in "pretex.m4" for a fuller explanation (and the macro definitions). +_1__ _fi__(0) -_include__(gdbVN.m4) -@c @smallbook -@c @cropmarks -@tex -\def\$#1${{#1}} % Kluge: collect RCS revision info without $...$ -\xdef\manvers{\$Revision$} % For use in headers, footers too -@end tex +_include__(gdbVN.m4)_dnl__ @c -@syncodeindex ky cp -@c FOR UPDATES LEADING TO THIS DRAFT, GDB CHANGELOG CONSULTED BETWEEN: -@c Fri Oct 11 23:27:06 1991 John Gilmore (gnu at cygnus.com) -@c Sat Dec 22 02:51:40 1990 John Gilmore (gnu at cygint) @ifinfo This file documents the GNU debugger _GDBN__. +@c !!set edition, date, version +This is Edition 4.00, December 1991, +of @cite{Using GDB: A Guide to the GNU Source-Level Debugger} +for GDB Version _GDB_VN__. + Copyright (C) 1988, 1989, 1990, 1991 Free Software Foundation, Inc. Permission is granted to make and distribute verbatim copies of @@ -69,17 +95,6 @@ except that the section entitled ``GNU General Public License'' may be included in a translation approved by the Free Software Foundation instead of in the original English. @end ifinfo -@c @smallbook -@setchapternewpage odd -_if__(_GENERIC__) -@settitle Using _GDBN__ (_GDB_VN__) -_fi__(_GENERIC__) -_if__(!_GENERIC__) -@settitle Using _GDBN__ _GDB_VN__ (_HOST__) -_fi__(!_GENERIC__) -@iftex -@finalout -@end iftex @titlepage @title Using _GDBN__ @subtitle A Guide to the GNU Source-Level Debugger @@ -87,20 +102,10 @@ _if__(!_GENERIC__) @subtitle On _HOST__ Systems _fi__(!_GENERIC__) @sp 1 -@subtitle _GDBN__ version _GDB_VN__ -@subtitle November 1991 -@c TEXI2ROFF-KILL -@c let's be nice to texi2roff, it can't be expected to know about hfill... -@author Richard M. Stallman@qquad @hfill Free Software Foundation -@author Roland H. Pesch@qquad @hfill Cygnus Support -@ignore -@c END TEXI2ROFF-KILL -@c sneaky, eh? -@author Richard M. Stallman, Free Software Foundation -@author Roland H. Pesch, Cygnus Support -@c TEXI2ROFF-KILL -@end ignore -@c END TEXI2ROFF-KILL +@c !!set edition, date, version +@subtitle Edition 4.00, for _GDBN__ version _GDB_VN__ +@subtitle December 1991 +@author by Richard M. Stallman and Roland H. Pesch @page @tex {\parskip=0pt @@ -132,31 +137,36 @@ instead of in the original English. @end titlepage @page -@node Top, Summary, (dir), (dir) @ifinfo -This file describes version _GDB_VN__ of GDB, the GNU symbolic debugger. +@node Top, Summary, (dir), (dir) +@top _GDBN__, the GNU symbolic debugger + +This file describes _GDBN__, the GNU symbolic debugger. + +@c !!set edition, date, version +This is Edition 4.00, December 1991, for GDB Version _GDB_VN__. @end ifinfo @menu * Summary:: Summary of _GDBN__ -* New Features:: New Features in _GDBN__ version _GDB_VN__ -* Sample Session:: A Sample _GDBN__ Session -* Invocation:: Getting In and Out of _GDBN__ -* Commands:: _GDBN__ Commands -* Running:: Running Programs Under _GDBN__ -* Stopping:: Stopping and Continuing -* Stack:: Examining the Stack -* Source:: Examining Source Files -* Data:: Examining Data -* Languages:: Using _GDBN__ with Different Languages -* Symbols:: Examining the Symbol Table -* Altering:: Altering Execution -* _GDBN__ Files:: _GDBN__'s Files -* Targets:: Specifying a Debugging Target +* New Features:: New features since _GDBN__ version 3.5 +* Sample Session:: A sample _GDBN__ session +* Invocation:: Getting in and out of _GDBN__ +* Commands:: _GDBN__ commands +* Running:: Running programs under _GDBN__ +* Stopping:: Stopping and continuing +* Stack:: Examining the stack +* Source:: Examining source files +* Data:: Examining data +* Languages:: Using _GDBN__ with different languages +* Symbols:: Examining the symbol table +* Altering:: Altering execution +* _GDBN__ Files:: _GDBN__'s files +* Targets:: Specifying a debugging target * Controlling _GDBN__:: Controlling _GDBN__ -* Sequences:: Canned Sequences of Commands +* Sequences:: Canned sequences of commands * Emacs:: Using _GDBN__ under GNU Emacs -* _GDBN__ Bugs:: Reporting Bugs in _GDBN__ +* _GDBN__ Bugs:: Reporting bugs in _GDBN__ * Renamed Commands:: * Installing _GDBN__:: Installing _GDBN__ * Copying:: GNU GENERAL PUBLIC LICENSE @@ -171,7 +181,7 @@ Summary of _GDBN__ Getting In and Out of _GDBN__ -* Starting _GDBN__:: Starting _GDBN__ +* Invoking _GDBN__:: Starting _GDBN__ * Leaving _GDBN__:: Leaving _GDBN__ * Shell Commands:: Shell Commands @@ -277,7 +287,7 @@ C and C++ Modula-2 * M2 Operators:: Built-in operators -* Builtin Func/Proc:: Built-in Functions and Procedures +* Built-In Func/Proc:: Built-in Functions and Procedures * M2 Constants:: Modula-2 Constants * M2 Defaults:: Default settings for Modula-2 * Deviations:: Deviations from standard Modula-2 @@ -289,7 +299,7 @@ Altering Execution * Assignment:: Assignment to Variables * Jumping:: Continuing at a Different Address -* Signaling:: Giving the Program a Signal +* Signaling:: Giving your program a Signal * Returning:: Returning from a Function * Calling:: Calling your Program's Functions * Patching:: Patching your Program @@ -362,10 +372,10 @@ Installing GDB The purpose of a debugger such as _GDBN__ is to allow you to see what is going on ``inside'' another program while it executes---or what another -program was doing at the moment it crashed. +program was doing at the moment it crashed.@refill _GDBN__ can do four main kinds of things (plus other things in support of -these) to help you catch bugs in the act: +these) to help you catch bugs in the act:@refill @itemize @bullet @item @@ -401,11 +411,10 @@ Typical software companies use copyrights to limit your freedoms; the Free Software Foundation uses the GPL to preserve these freedoms. Fundamentally, the General Public License is a license which says that -you have these freedoms and that you can't take these freedoms away +you have these freedoms and that you cannot take these freedoms away from anyone else. -@c FIXME: (passim) go through all xrefs, expanding to use text headings -For full details, @pxref{Copying}. +For full details, @pxref{Copying, ,GNU GENERAL PUBLIC LICENSE}. @node Contributors, , Free Software, Summary @unnumberedsec Contributors to GDB @@ -427,10 +436,10 @@ omitted from this list, we would like to add your names! So that they may not regard their long labor as thankless, we particularly thank those who shepherded GDB through major releases: John -Gilmore (releases _GDB_VN__, 4.1, 4.0); Jim Kingdon (releases 3.9, 3.5, -3.4, 3.3); and Randy Smith (releases 3.2, 3.1, 3.0). As major +Gilmore (releases _GDB_VN__, 4.2, 4.1, 4.0); Jim Kingdon (releases 3.9, +3.5, 3.4, 3.3); and Randy Smith (releases 3.2, 3.1, 3.0). As major maintainer of GDB for some period, each contributed significantly to the -structure, stability, and capabilities of the entire debugger. +structure, stability, and capabilities of the entire debugger.@refill Richard Stallman, assisted at various times by Pete TerMaat, Chris Hanson, and Richard Mlynarik, handled releases through 2.8. @@ -440,26 +449,25 @@ with significant additional contributions from Per Bothner. James Clark wrote the GNU C++ demangler. Early work on C++ was by Peter TerMaat (who also did much general update work leading to release 3.0). -GDB _GDB_VN__ uses the BFD subroutine library to examine multiple -object-file formats; BFD was a joint project of V. Gumby -Henkel-Wallace, Rich Pixley, Steve Chamberlain, and John Gilmore. +GDB 4 uses the BFD subroutine library to examine multiple object-file +formats; BFD was a joint project of V. Gumby Henkel-Wallace, Rich +Pixley, Steve Chamberlain, and John Gilmore. -David Johnson wrote the original COFF support; Pace Willison did -the original support for encapsulated COFF. +David Johnson wrote the original COFF support; Pace Willison did the +original support for encapsulated COFF. Adam de Boor and Bradley Davis contributed the ISI Optimum V support. Per Bothner, Noboyuki Hikichi, and Alessandro Forin contributed MIPS -support. Jean-Daniel Fekete contributed Sun 386i support. Chris -Hanson improved the HP9000 support. Noboyuki Hikichi and Tomoyuki -Hasei contributed Sony/News OS 3 support. David Johnson contributed -Encore Umax support. Jyrki Kuoppala contributed Altos 3068 support. -Keith Packard contributed NS32K support. Doug Rabson contributed -Acorn Risc Machine support. Chris Smith contributed Convex support -(and Fortran debugging). Jonathan Stone contributed Pyramid support. -Michael Tiemann contributed SPARC support. Tim Tucker contributed -support for the Gould NP1 and Gould Powernode. Pace Willison -contributed Intel 386 support. Jay Vosburgh contributed Symmetry -support. +support. Jean-Daniel Fekete contributed Sun 386i support. Chris Hanson +improved the HP9000 support. Noboyuki Hikichi and Tomoyuki Hasei +contributed Sony/News OS 3 support. David Johnson contributed Encore +Umax support. Jyrki Kuoppala contributed Altos 3068 support. Keith +Packard contributed NS32K support. Doug Rabson contributed Acorn Risc +Machine support. Chris Smith contributed Convex support (and Fortran +debugging). Jonathan Stone contributed Pyramid support. Michael +Tiemann contributed SPARC support. Tim Tucker contributed support for +the Gould NP1 and Gould Powernode. Pace Willison contributed Intel 386 +support. Jay Vosburgh contributed Symmetry support. Rich Schaefer and Peter Schauer helped with support of SunOS shared libraries. @@ -467,16 +475,15 @@ libraries. Jay Fenlason and Roland McGrath ensured that GDB and GAS agree about several machine instruction sets. -Patrick Duval, Ted Goldstein, Vikram Koka and Glenn Engel helped -develop remote debugging. Intel Corporation and Wind River Systems -contributed remote debugging modules for their products. +Patrick Duval, Ted Goldstein, Vikram Koka and Glenn Engel helped develop +remote debugging. Intel Corporation and Wind River Systems contributed +remote debugging modules for their products. -Brian Fox is the author of the readline libraries providing -command-line editing and command history. +Brian Fox is the author of the readline libraries providing command-line +editing and command history. -Andrew Beers of SUNY Buffalo wrote the language-switching code and -the Modula-2 support, and contributed the Languages chapter of this -manual. +Andrew Beers of SUNY Buffalo wrote the language-switching code and the +Modula-2 support, and contributed the Languages chapter of this manual. @node New Features, Sample Session, Summary, Top @unnumbered New Features since _GDBN__ version 3.5 @@ -517,7 +524,7 @@ the other GNU binary utilities are being converted to use it. Compile-time configuration (to select a particular architecture and operating system) is much easier. The script @code{configure} now allows you to configure _GDBN__ as either a native debugger or a -cross-debugger. @xref{Installing _GDBN__} for details on how to +cross-debugger. @xref{Installing _GDBN__}, for details on how to configure and on what architectures are now available. @item Interaction @@ -552,11 +559,11 @@ of your program, and the latter refer to the state of _GDBN__ itself. @xref{Renamed Commands}, for details on what commands were renamed. @item Shared Libraries -_GDBN__ _GDB_VN__ can debug programs and core files that use SunOS shared +_GDBN__ 4 can debug programs and core files that use SunOS shared libraries. @item Reference Card -_GDBN__ _GDB_VN__ has a reference card; @xref{Formatting Documentation} for +_GDBN__ 4 has a reference card; @xref{Formatting Documentation} for instructions on printing it. @item Work in Progress @@ -585,7 +592,7 @@ processor) exhibits the following bug: sometimes, when we change its quote strings from the default, the commands used to capture one macro's definition in another stop working. In the following short @code{m4} session, we define a macro @code{foo} which expands to @code{0000}; we -then use the @code{m4} builtin @code{defn} to define @code{bar} as the +then use the @code{m4} built-in @code{defn} to define @code{bar} as the same thing. However, when we change the open quote string to @code{} and the close quote string to @code{}, the same procedure fails to define a new synonym @code{baz}: @@ -626,17 +633,17 @@ GDB _GDB_VN__, Copyright 1991 Free Software Foundation, Inc... @end smallexample @noindent -_GDBN__ reads only enough symbol data to know where to find the rest -when needed; as a result, the first prompt comes up very quickly. We -then tell _GDBN__ to use a narrower display width than usual, so -that examples will fit in this manual. +_GDBN__ reads only enough symbol data to know where to find the +rest when needed; as a result, the first prompt comes up very +quickly. We now tell _GDBN__ to use a narrower display width than +usual, so that examples will fit in this manual.@refill @smallexample (_GDBP__) @i{set width 70} @end smallexample @noindent -Let's see how the @code{m4} builtin @code{changequote} works. +Let's see how the @code{m4} built-in @code{changequote} works. Having looked at the source, we know the relevant subroutine is @code{m4_changequote}, so we set a breakpoint there with _GDBN__'s @code{break} command. @@ -697,11 +704,12 @@ set_quotes (lq=0x34c78 "", rq=0x34c88 "") @end smallexample @noindent -The summary display showing the subroutine where @code{m4} is now -suspended (and its arguments) is called a stack frame display. We can -use the @code{backtrace} command (which can also be spelled @code{bt}), -to see where we are in the stack: it displays a stack frame for each -active subroutine. +The display that shows the subroutine where @code{m4} is now +suspended (and its arguments) is called a stack frame display. It +shows a summary of the stack. We can use the @code{backtrace} +command (which can also be spelled @code{bt}), to see where we are +in the stack as a whole: the @code{backtrace} command displays a +stack frame for each active subroutine. @smallexample (_GDBP__) @i{bt} @@ -835,34 +843,38 @@ _1__@end smallexample @node Invocation, Commands, Sample Session, Top @chapter Getting In and Out of _GDBN__ +Type @kbd{gdb} or @kbd{gdb @var{program} @var{core}} to start GDB +and type @kbd{quit} or @kbd{C-d} to exit. + @menu -* Starting _GDBN__:: Starting _GDBN__ +* Invoking _GDBN__:: Starting _GDBN__ * Leaving _GDBN__:: Leaving _GDBN__ * Shell Commands:: Shell Commands @end menu -@node Starting _GDBN__, Leaving _GDBN__, Invocation, Invocation +@node Invoking _GDBN__, Leaving _GDBN__, Invocation, Invocation @section Starting _GDBN__ -_GDBN__ is invoked with the shell command @code{_GDBP__}. Once started, +Invoke _GDBN__ with the shell command @code{_GDBP__}. Once started, it reads commands from the terminal until you tell it to exit. You can run @code{_GDBP__} with no arguments or options; but the most usual way to start _GDBN__ is with one argument or two, specifying an executable program as the argument: @example -_GDBP__ program +_GDBP__ @var{program} @end example @noindent -You can also start with both an executable program and a core file specified: +You can also start with both an executable program and a core file +specified: @example -_GDBP__ program core +_GDBP__ @var{program} @var{core} @end example You can, instead, specify a process ID as a second argument, if you want to debug a running process: @example -_GDBP__ program 1234 +_GDBP__ @var{program} 1234 @end example @noindent would attach _GDBN__ to process @code{1234} (unless you also have a file @@ -870,12 +882,17 @@ named @file{1234}; _GDBN__ does check for a core file first). @noindent You can further control how _GDBN__ starts up by using command-line -options. _GDBN__ itself can remind you of the options available: +options. _GDBN__ itself can remind you of the options available. + +@noindent +Type + @example _GDBP__ -help @end example + @noindent -will display all available options and briefly describe their use +to display all available options and briefly describe their use (@samp{_GDBP__ -h} is a shorter equivalent). All options and command line arguments you give are processed @@ -890,19 +907,23 @@ _include__(gdbinv-m.m4)_dnl__ _fi__(!_GENERIC__) @end menu -@node File Options, Mode Options, Starting _GDBN__, Starting _GDBN__ +@node File Options, Mode Options, Invoking _GDBN__, Invoking _GDBN__ @subsection Choosing Files -As shown above, any arguments other than options specify an executable -file and core file (or process ID); that is, the first argument -encountered with no associated option flag is equivalent to a @samp{-se} -option, and the second, if any, is equivalent to a @samp{-c} option if -it's the name of a file. -Many options have both long and short forms; both are shown here. The -long forms are also recognized if you truncate them, so long as enough -of the option is present to be unambiguous. (If you prefer, you can -flag option arguments with @samp{+} rather than @samp{-}, though we -illustrate the more usual convention.) +When _GDBN__ starts, it reads any arguments other than options as +specifying an executable file and core file (or process ID). This is +the same as if the arguments were specified by the @samp{-se} and +@samp{-c} options respectively. (_GDBN__ reads the first argument +that does not have an associated option flag as equivalent to the +@samp{-se} option followed by that argument; and the second argument +that does not have an associated option flag, if any, as equivalent to +the @samp{-c} option followed by that argument.) + +Many options have both long and short forms; both are shown in the +following list. _GDBN__ also recognizes the long forms if you truncate +them, so long as enough of the option is present to be unambiguous. +(If you prefer, you can flag option arguments with @samp{--} rather +than @samp{-}, though we illustrate the more usual convention.) @table @code @item -symbols=@var{file} @@ -933,11 +954,13 @@ Add @var{directory} to the path to search for source files. @end table _if__(!_GENERIC__) -@node Mode Options, Mode Options, File Options, Starting _GDBN__ +@node Mode Options, Mode Options, File Options, Invoking _GDBN__ _fi__(!_GENERIC__) _if__(_GENERIC__) -@node Mode Options, , File Options, Starting _GDBN__ -_fi__(_GENERIC__) +@node Mode Options, , File Options, Invoking _GDBN__ +_fi__(_GENERIC__) +You can run _GDBN__ in various alternative modes---for example, in +batch mode or quiet mode. @subsection Choosing Modes @table @code @@ -978,7 +1001,7 @@ instead of the current directory. Emacs sets this option when it runs _GDBN__ as a subprocess. It tells _GDBN__ to output the full file name and line number in a standard, recognizable fashion each time a stack frame is displayed (which -includes each time the program stops). This recognizable format looks +includes each time your program stops). This recognizable format looks like two @samp{\032} characters, followed by the file name, line number and character position separated by colons, and a newline. The Emacs-to-_GDBN__ interface program uses the two @samp{\032} characters as @@ -990,14 +1013,14 @@ interface used by _GDBN__ for remote debugging. @item -tty=@var{device} Run using @var{device} for your program's standard input and output. -@c FIXME: kingdon thinks there's more to -tty. Investigate. +@c FIXME: kingdon thinks there is more to -tty. Investigate. @end table _if__(!_GENERIC__) _include__(gdbinv-s.m4) _fi__(!_GENERIC__) -@node Leaving _GDBN__, Shell Commands, Starting _GDBN__, Invocation +@node Leaving _GDBN__, Shell Commands, Invoking _GDBN__, Invocation @section Leaving _GDBN__ @cindex exiting _GDBN__ @table @code @@ -1016,12 +1039,12 @@ character at any time because _GDBN__ does not allow it to take effect until a time when it is safe. If you've been using _GDBN__ to control an attached process or device, -you can release it with the @code{detach} command; @pxref{Attach}. +you can release it with the @code{detach} command; @pxref{Attach, ,Debugging an Already-Running Process}.. @node Shell Commands, , Leaving _GDBN__, Invocation @section Shell Commands If you need to execute occasional shell commands during your -debugging session, there's no need to leave or suspend _GDBN__; you can +debugging session, there is no need to leave or suspend _GDBN__; you can just use the @code{shell} command. @table @code @@ -1035,7 +1058,7 @@ for the name of the shell to run. Otherwise _GDBN__ uses @end table The utility @code{make} is often needed in development environments. -You don't have to use the @code{shell} command for this purpose in _GDBN__: +You do not have to use the @code{shell} command for this purpose in _GDBN__: @table @code @item make @var{make-args} @@ -1048,6 +1071,9 @@ arguments. This is equivalent to @samp{shell make @var{make-args}}. @node Commands, Running, Invocation, Top @chapter _GDBN__ Commands +You can abbreviate GDB command if that abbreviation is unambiguous; +and you can repeat certain GDB commands by typing just @key{RET}. + @menu * Command Syntax:: Command Syntax * Help:: Getting Help @@ -1085,14 +1111,14 @@ exactly as typed. This permits easy scanning of source or memory. _GDBN__ can also use @key{RET} in another way: to partition lengthy output, in a way similar to the common utility @code{more} -(@pxref{Screen Size}). Since it's easy to press one @key{RET} too many +(@pxref{Screen Size}). Since it is easy to press one @key{RET} too many in this situation, _GDBN__ disables command repetition after any command that generates this sort of display. @kindex # @cindex comment A line of input starting with @kbd{#} is a comment; it does nothing. -This is useful mainly in command files (@xref{Command Files}). +This is useful mainly in command files (@pxref{Command Files}). @node Help, , Command Syntax, Commands @section Getting Help @@ -1159,9 +1185,7 @@ and @code{show} to inquire about the state of your program, or the state of _GDBN__ itself. Each command supports many topics of inquiry; this manual introduces each of them in the appropriate context. The listings under @code{info} and under @code{show} in the Index point to -all the sub-commands. -@c FIXME: @pxref{Index} used to be here, but even though it shows up in -@c FIXME...the 'aux' file with a pageno the xref can't find it. +all the sub-commands. @xref{Index}. @c @group @table @code @@ -1203,7 +1227,7 @@ exceptional in lacking corresponding @code{set} commands: Show what version of _GDBN__ is running. You should include this information in _GDBN__ bug-reports. If multiple versions of _GDBN__ are in use at your site, you may occasionally want to make sure what version -of _GDBN__ you're running; as _GDBN__ evolves, new commands are +of _GDBN__ you are running; as _GDBN__ evolves, new commands are introduced, and old ones may wither away. The version number is also announced when you start _GDBN__ with no arguments. @@ -1248,8 +1272,8 @@ executables containing debugging information. The GNU C compiler supports @samp{-g} with or without @samp{-O}, making it possible to debug optimized code. We recommend that you @emph{always} use -@samp{-g} whenever you compile a program. You may think the program is -correct, but there's no sense in pushing your luck. +@samp{-g} whenever you compile a program. You may think your program is +correct, but there is no sense in pushing your luck. Some things do not work as well with @samp{-g -O} as with just @samp{-g}, particularly on machines with instruction scheduling. If in @@ -1266,7 +1290,7 @@ format; if your GNU C compiler has this option, do not use it. If your program includes archives made with the @code{ar} program, and if the object files used as input to @code{ar} were compiled without the @samp{-g} option and have names longer than 15 characters, _GDBN__ will get -confused reading the program's symbol table. No error message will be +confused reading your program's symbol table. No error message will be given, but _GDBN__ may behave strangely. The reason for this problem is a deficiency in the Unix archive file format, which cannot represent file names longer than 15 characters. @@ -1276,7 +1300,6 @@ option or use shorter file names. Alternatively, use a version of GNU @code{ar} dated more recently than August 1989. @end ignore - @node Starting, Arguments, Compilation, Running @section Starting your Program @cindex starting @@ -1291,67 +1314,71 @@ _if__(_VXWORKS__) (except on VxWorks) _fi__(_VXWORKS__) with an argument to _GDBN__ -(@pxref{Invocation}), or using the @code{file} or @code{exec-file} -command (@pxref{Files}). +(@pxref{Invocation, ,Getting In and Out of _GDBN__}), or using the @code{file} or @code{exec-file} +command (@pxref{Files, ,Commands to Specify Files}). @refill @end table -@c FIXME explain or avoid "target" here? -On targets that support processes, @code{run} creates an inferior -process and makes that process run your program. On other targets, -@code{run} jumps to the start of the program. +If you are running your program in an execution environment that +supports processes, @code{run} creates an inferior process and makes +that process run your program. (In environments without processes, +@code{run} jumps to the start of your program.) The execution of a program is affected by certain information it receives from its superior. _GDBN__ provides ways to specify this -information, which you must do @i{before} starting the program. (You -can change it after starting the program, but such changes will only affect -the program the next time you start it.) This information may be +information, which you must do @i{before} starting your program. (You +can change it after starting your program, but such changes will only affect +your program the next time you start it.) This information may be divided into four categories: @table @asis @item The @i{arguments.} -You specify the arguments to give your program as the arguments of the -@code{run} command. If a shell is available on your target, the shell -is used to pass the arguments, so that you may use normal conventions -(such as wildcard expansion or variable substitution) in -describing the arguments. In Unix systems, you can control which shell -is used with the @code{SHELL} environment variable. @xref{Arguments}.@refill +Specify the arguments to give your program as the arguments of the +@code{run} command. If a shell is available on your target, the +shell is used to pass the arguments, so that you may use normal +conventions (such as wildcard expansion or variable substitution) +in describing the arguments. In Unix systems, you can control +which shell is used with the @code{SHELL} environment variable. +@xref{Arguments, ,Your Program's Arguments}.@refill @item The @i{environment.} Your program normally inherits its environment from _GDBN__, but you can use the _GDBN__ commands @code{set environment} and @code{unset environment} to change parts of the environment that will be given to -the program. @xref{Environment}.@refill +your program. @xref{Environment, ,Your Program's Environment}.@refill @item The @i{working directory.} Your program inherits its working directory from _GDBN__. You can set _GDBN__'s working directory with the @code{cd} command in _GDBN__. -@xref{Working Directory}. +@xref{Working Directory, ,Your Program's Working Directory}. @item The @i{standard input and output.} Your program normally uses the same device for standard input and standard output as _GDBN__ is using. You can redirect input and output in the @code{run} command line, or you can use the @code{tty} command to set a different device for your program. -@xref{Input/Output}. +@xref{Input/Output, Your Program's Input and Output}. @cindex pipes -@emph{Warning:} While input and output redirection work, you can't use -pipes to pass the output of the program you're debugging to another +@emph{Warning:} While input and output redirection work, you cannot use +pipes to pass the output of the program you are debugging to another program; if you attempt this, _GDBN__ is likely to wind up debugging the wrong program. @end table -When you issue the @code{run} command, your program begins to execute -immediately. @xref{Stopping}, for discussion of how to arrange for your -program to stop. Once your program has been started by the @code{run} -command (and then stopped), you may evaluate expressions that involve -calls to functions in the inferior, using the @code{print} or -@code{call} commands. @xref{Data}. +@c FIXME: Rewrite following paragraph, especially its third sentence. +When you issue the @code{run} command, your program begins to +execute immediately. @xref{Stopping, ,Stopping and Continuing}, for +discussion of how to arrange for your program to stop. Once your +program has been started by the @code{run} command (and then stopped), +you may evaluate expressions that involve calls to functions in the +inferior, using the @code{print} or @code{call} commands. @xref{Data, +,Examining Data}. -If the modification time of your symbol file has changed since the last -time _GDBN__ read its symbols, _GDBN__ will discard its symbol table and re-read -it. In this process, it tries to retain your current breakpoints. +If the modification time of your symbol file has changed since the +last time _GDBN__ read its symbols, _GDBN__ will discard its symbol +table and re-read it. When it does this, _GDBN__ tries to retain your +current breakpoints. @node Arguments, Environment, Starting, Running @section Your Program's Arguments @@ -1359,7 +1386,7 @@ it. In this process, it tries to retain your current breakpoints. @cindex arguments (to your program) The arguments to your program can be specified by the arguments of the @code{run} command. They are passed to a shell, which expands wildcard -characters and performs redirection of I/O, and thence to the program. +characters and performs redirection of I/O, and thence to your program. _GDBN__ uses the shell indicated by your environment variable @code{SHELL} if it exists; otherwise, _GDBN__ uses @code{/bin/sh}. @@ -1389,7 +1416,7 @@ their values. Environment variables conventionally record such things as your user name, your home directory, your terminal type, and your search path for programs to run. Usually you set up environment variables with the shell and they are inherited by all the other programs you run. When -debugging, it can be useful to try running the program with a modified +debugging, it can be useful to try running your program with a modified environment without having to start _GDBN__ over again. @table @code @@ -1406,7 +1433,7 @@ working directory at the time _GDBN__ searches the path. If you use @samp{.} instead, it refers to the directory where you executed the @code{path} command. _GDBN__ fills in the current path where needed in the @var{directory} argument, before adding it to the search path. -@c 'path' is explicitly nonrepeatable, but RMS points out it's silly to +@c 'path' is explicitly nonrepeatable, but RMS points out it is silly to @c document that, since repeating it would be a no-op. @item show paths @@ -1417,7 +1444,7 @@ environment variable). @item show environment @r{[}@var{varname}@r{]} @kindex show environment Print the value of environment variable @var{varname} to be given to -your program when it starts. If you don't supply @var{varname}, +your program when it starts. If you do not supply @var{varname}, print the names and values of all environment variables to be given to your program. You can abbreviate @code{environment} as @code{env}. @@ -1429,7 +1456,7 @@ be any string; the values of environment variables are just strings, and any interpretation is supplied by your program itself. The @var{value} parameter is optional; if it is eliminated, the variable is set to a null value. -@c "any string" here doesn't include leading, trailing +@c "any string" here does not include leading, trailing @c blanks. Gnu asks: does anyone care? For example, this command: @@ -1462,7 +1489,7 @@ process (typically the shell), but you can specify a new working directory in _GDBN__ with the @code{cd} command. The _GDBN__ working directory also serves as a default for the commands -that specify files for _GDBN__ to operate on. @xref{Files}. +that specify files for _GDBN__ to operate on. @xref{Files, ,Commands to Specify Files}. @table @code @item cd @var{directory} @@ -1493,7 +1520,7 @@ Displays _GDBN__'s recorded information about the terminal modes your program is using. @end table -You can redirect the program's input and/or output using shell +You can redirect your program's input and/or output using shell redirection with the @code{run} command. For example, _0__@example @@ -1501,11 +1528,11 @@ run > outfile _1__@end example @noindent -starts the program, diverting its output to the file @file{outfile}. +starts your program, diverting its output to the file @file{outfile}. @kindex tty @cindex controlling terminal -Another way to specify where the program should do input and output is +Another way to specify where your program should do input and output is with the @code{tty} command. This command accepts a file name as argument, and causes this file to be the default for future @code{run} commands. It also resets the controlling terminal for the child @@ -1553,7 +1580,7 @@ process. When using @code{attach}, you should first use the @code{file} command to specify the program running in the process and load its symbol table. -@xref{Files}. +@xref{Files, ,Commands to Specify Files}. The first thing _GDBN__ does after arranging to debug the specified process is to stop it. You can examine and modify an attached process @@ -1579,7 +1606,7 @@ If you exit _GDBN__ or use the @code{run} command while you have an attached process, you kill that process. By default, you will be asked for confirmation if you try to do either of these things; you can control whether or not you need to confirm by using the @code{set confirm} command -(@pxref{Messages/Warnings}). +(@pxref{Messages/Warnings, ,Optional Warnings and Messages}). @node Kill Process, , Attach, Running @c @group @@ -1596,13 +1623,13 @@ running process. _GDBN__ ignores any core dump file while your program is running. @c @end group -On some operating systems, a program can't be executed outside _GDBN__ +On some operating systems, a program cannot be executed outside _GDBN__ while you have breakpoints set on it inside _GDBN__. You can use the -@code{kill} command in this situation to permit running the program +@code{kill} command in this situation to permit running your program outside the debugger. The @code{kill} command is also useful if you wish to recompile and -relink the program, since on many systems it is impossible to modify an +relink your program, since on many systems it is impossible to modify an executable file while it is running in a process. In this case, when you next type @code{run}, _GDBN__ will notice that the file has changed, and will re-read the symbol table (while trying to preserve your current @@ -1612,7 +1639,7 @@ breakpoint settings). @chapter Stopping and Continuing The principal purpose of using a debugger is so that you can stop your -program before it terminates; or so that, if the program runs into +program before it terminates; or so that, if your program runs into trouble, you can investigate and find out why. Inside _GDBN__, your program may stop for any of several reasons, such @@ -1641,27 +1668,29 @@ running or not, what process it is, and why it stopped. @cindex breakpoints A @dfn{breakpoint} makes your program stop whenever a certain point in -the program is reached. For each breakpoint, you can add various -conditions to control in finer detail whether the program will stop. +your program is reached. For each breakpoint, you can add various +conditions to control in finer detail whether your program will stop. You can set breakpoints with the @code{break} command and its variants -(@pxref{Set Breaks}), to specify the place where the program should stop -by line number, function name or exact address in the program. In -languages with exception handling (such as GNU C++), you can also set -breakpoints where an exception is raised (@pxref{Exception Handling}). +(@pxref{Set Breaks, ,Setting Breakpoints}), to specify the place where +your program should stop by line number, function name or exact address +in your program. In languages with exception handling (such as GNU +C++), you can also set breakpoints where an exception is raised +(@pxref{Exception Handling, ,Breakpoints and Exceptions}).@refill @cindex watchpoints -A @dfn{watchpoint} is a special breakpoint that stops your program when -the value of an expression changes. You must use a different command to -set watchpoints (@pxref{Set Watchpoints}), but aside from that, you can -manage a watchpoint like any other breakpoint: you enable, disable, and -delete both breakpoints and watchpoints using the same commands. +A @dfn{watchpoint} is a special breakpoint that stops your program +when the value of an expression changes. You must use a different +command to set watchpoints (@pxref{Set Watchpoints, ,Setting +Watchpoints}), but aside from that, you can manage a watchpoint like +any other breakpoint: you enable, disable, and delete both breakpoints +and watchpoints using the same commands.@refill Each breakpoint or watchpoint is assigned a number when it is created; these numbers are successive integers starting with one. In many of the commands for controlling various features of breakpoints you use the breakpoint number to say which breakpoint you want to change. Each breakpoint may be @dfn{enabled} or @dfn{disabled}; if disabled, it has -no effect on the program until you enable it again. +no effect on your program until you enable it again. @menu * Set Breaks:: Setting Breakpoints @@ -1704,7 +1733,7 @@ at which execution stopped in the currently selected frame. @item break @var{linenum} Set a breakpoint at line @var{linenum} in the current source file. That file is the last file whose source text was printed. This -breakpoint will stop the program just before it executes any of the +breakpoint will stop your program just before it executes any of the code on that line. @item break @var{filename}:@var{linenum} @@ -1718,40 +1747,41 @@ functions. @item break *@var{address} Set a breakpoint at address @var{address}. You can use this to set -breakpoints in parts of the program which do not have debugging +breakpoints in parts of your program which do not have debugging information or source files. @item break -When called without any arguments, @code{break} sets a breakpoint at the -next instruction to be executed in the selected stack frame -(@pxref{Stack}). In any selected frame but the innermost, this will -cause the program to stop as soon as control returns to that frame. -This is similar to the effect of a @code{finish} command in the frame -inside the selected frame---except that @code{finish} doesn't leave an -active breakpoint. If you use @code{break} without an argument in the -innermost frame, _GDBN__ will stop the next time it reaches the current -location; this may be useful inside loops. +When called without any arguments, @code{break} sets a breakpoint at +the next instruction to be executed in the selected stack frame +(@pxref{Stack, ,Examining the Stack}). In any selected frame but the +innermost, this will cause your program to stop as soon as control +returns to that frame. This is similar to the effect of a +@code{finish} command in the frame inside the selected frame---except +that @code{finish} does not leave an active breakpoint. If you use +@code{break} without an argument in the innermost frame, _GDBN__ will +stop the next time it reaches the current location; this may be useful +inside loops.@refill _GDBN__ normally ignores breakpoints when it resumes execution, until at least one instruction has been executed. If it did not do this, you would be unable to proceed past a breakpoint without first disabling the breakpoint. This rule applies whether or not the breakpoint already -existed when the program stopped. +existed when your program stopped. @item break @dots{} if @var{cond} Set a breakpoint with condition @var{cond}; evaluate the expression @var{cond} each time the breakpoint is reached, and stop only if the value is nonzero---that is, if @var{cond} evaluates as true. @samp{@dots{}} stands for one of the possible arguments described above -(or no argument) specifying where to break. @xref{Conditions}, for more -information on breakpoint conditions. +(or no argument) specifying where to break. @xref{Conditions, ,Break +Conditions}, for more information on breakpoint conditions. @item tbreak @var{args} @kindex tbreak Set a breakpoint enabled only for one stop. @var{args} are the same as for the @code{break} command, and the breakpoint is set in the same -way, but the breakpoint is automatically disabled the first time it -is hit. @xref{Disabling}. +way, but the breakpoint is automatically disabled after the first time your +program stops there. @xref{Disabling, ,Disabling Breakpoints}. @item rbreak @var{regex} @kindex rbreak @@ -1773,18 +1803,19 @@ classes. @item info breakpoints @r{[}@var{n}@r{]} @item info break @r{[}@var{n}@r{]} Print a list of all breakpoints (but not watchpoints) set and not -deleted, showing their numbers, where in the program they are, and any +deleted, showing their numbers, where in your program they are, and any special features in use for them. Disabled breakpoints are included in the list, but marked as disabled. @code{info break} with a breakpoint -number @var{n} as argument lists only that breakpoint. The convenience -variable @code{$_} and the default examining-address for the @code{x} -command are set to the address of the last breakpoint listed -(@pxref{Memory}). The equivalent command for watchpoints is @code{info -watch}. @end table +number @var{n} as argument lists only that breakpoint. The +convenience variable @code{$_} and the default examining-address for +the @code{x} command are set to the address of the last breakpoint +listed (@pxref{Memory, ,Examining Memory}). The equivalent command +for watchpoints is @code{info watch}. @end table -_GDBN__ allows you to set any number of breakpoints at the same place in the -program. There is nothing silly or meaningless about this. When the -breakpoints are conditional, this is even useful (@pxref{Conditions}). +_GDBN__ allows you to set any number of breakpoints at the same place +in your program. There is nothing silly or meaningless about this. +When the breakpoints are conditional, this is even useful +(@pxref{Conditions, ,Break Conditions}). @node Set Watchpoints, Exception Handling, Set Breaks, Breakpoints @subsection Setting Watchpoints @@ -1815,8 +1846,8 @@ This command prints a list of watchpoints; it is otherwise similar to @cindex exception handlers Some languages, such as GNU C++, implement exception handling. You can -use _GDBN__ to examine what caused the program to raise an exception, -and to list the exceptions the program is prepared to handle at a +use _GDBN__ to examine what caused your program to raise an exception, +and to list the exceptions your program is prepared to handle at a given point in time. @table @code @@ -1827,8 +1858,8 @@ You can set breakpoints at active exception handlers by using the to catch. @end table -You can use @code{info catch} to list active exception handlers; -@pxref{Frame Info}. +You can use @code{info catch} to list active exception handlers. +@xref{Frame Info, ,Information About a Frame}. There are currently some limitations to exception handling in _GDBN__. These will be corrected in a future release. @@ -1838,7 +1869,7 @@ These will be corrected in a future release. If you call a function interactively, _GDBN__ normally returns control to you when the function has finished executing. If the call raises an exception, however, the call may bypass the mechanism that -returns control to the user and cause the program to simply continue +returns control to you and cause your program to simply continue running until it hits a breakpoint, catches a signal that _GDBN__ is listening for, or exits. @item @@ -1849,7 +1880,7 @@ You cannot interactively install an exception handler. @cindex raise exceptions Sometimes @code{catch} is not the best way to debug exception handling: -if you need to know exactly where an exception is raised, it's better to +if you need to know exactly where an exception is raised, it is better to stop @emph{before} the exception handler is called, since that way you can see the stack before any unwinding takes place. If you set a breakpoint in an exception handler instead, it may not be easy to find @@ -1869,12 +1900,13 @@ which has the following ANSI C interface: @noindent To make the debugger catch all exceptions before any stack unwinding takes place, set a breakpoint on @code{__raise_exception} -(@pxref{Breakpoints}). +(@pxref{Breakpoints, ,Breakpoints Watchpoints and Exceptions}). -With a conditional breakpoint (@xref{Conditions}) that depends on the -value of @var{id}, you can stop your program when a specific exception -is raised. You can use multiple conditional breakpoints to stop the -program when any of a number of exceptions are raised. +With a conditional breakpoint (@pxref{Conditions, ,Break Conditions}) +that depends on the value of @var{id}, you can stop your program when +a specific exception is raised. You can use multiple conditional +breakpoints to stop your program when any of a number of exceptions are +raised. @node Delete Breaks, Disabling, Exception Handling, Breakpoints @subsection Deleting Breakpoints @@ -1882,12 +1914,12 @@ program when any of a number of exceptions are raised. @cindex clearing breakpoints, watchpoints @cindex deleting breakpoints, watchpoints It is often necessary to eliminate a breakpoint or watchpoint once it -has done its job and you no longer want the program to stop there. This +has done its job and you no longer want your program to stop there. This is called @dfn{deleting} the breakpoint. A breakpoint that has been deleted no longer exists; it is forgotten. With the @code{clear} command you can delete breakpoints according to -where they are in the program. With the @code{delete} command you can +where they are in your program. With the @code{delete} command you can delete individual breakpoints or watchpoints by specifying their breakpoint numbers. @@ -1899,9 +1931,9 @@ when you continue execution without changing the execution address. @item clear @kindex clear Delete any breakpoints at the next instruction to be executed in the -selected stack frame (@pxref{Selection}). When the innermost frame -is selected, this is a good way to delete a breakpoint that the program -just stopped at. +selected stack frame (@pxref{Selection, ,Selecting a Frame}). When +the innermost frame is selected, this is a good way to delete a +breakpoint where your program just stopped. @item clear @var{function} @itemx clear @var{filename}:@var{function} @@ -1935,23 +1967,23 @@ You disable and enable breakpoints and watchpoints with the @code{enable} and @code{disable} commands, optionally specifying one or more breakpoint numbers as arguments. Use @code{info break} or @code{info watch} to print a list of breakpoints or watchpoints if you -don't know which numbers to use. +do not know which numbers to use. A breakpoint or watchpoint can have any of four different states of enablement: @itemize @bullet @item -Enabled. The breakpoint will stop the program. A breakpoint set +Enabled. The breakpoint will stop your program. A breakpoint set with the @code{break} command starts out in this state. @item -Disabled. The breakpoint has no effect on the program. +Disabled. The breakpoint has no effect on your program. @item -Enabled once. The breakpoint will stop the program, but +Enabled once. The breakpoint will stop your program, but when it does so it will become disabled. A breakpoint set with the @code{tbreak} command starts out in this state. @item -Enabled for deletion. The breakpoint will stop the program, but +Enabled for deletion. The breakpoint will stop your program, but immediately after it does so it will be deleted permanently. @end itemize @@ -1973,23 +2005,23 @@ case the breakpoint is enabled again later. You may abbreviate @kindex enable breakpoints @kindex enable Enable the specified breakpoints (or all defined breakpoints). They -become effective once again in stopping the program. +become effective once again in stopping your program. @item enable @r{[}breakpoints@r{]} once @var{bnums}@dots{} Enable the specified breakpoints temporarily. Each will be disabled -again the next time it stops the program. +again the next time it stops your program. @item enable @r{[}breakpoints@r{]} delete @var{bnums}@dots{} Enable the specified breakpoints to work once and then die. Each of -the breakpoints will be deleted the next time it stops the program. +the breakpoints will be deleted the next time it stops your program. @end table -Save for a breakpoint set with @code{tbreak} (@pxref{Set Breaks}), -breakpoints that you set are initially enabled; subsequently, they become -disabled or enabled only when you use one of the commands above. (The -command @code{until} can set and delete a breakpoint of its own, but it -will not change the state of your other breakpoints; -@pxref{Continuing and Stepping}.) +Save for a breakpoint set with @code{tbreak} (@pxref{Set Breaks, +,Setting Breakpoints}), breakpoints that you set are initially +enabled; subsequently, they become disabled or enabled only when you +use one of the commands above. (The command @code{until} can set and +delete a breakpoint of its own, but it will not change the state of +your other breakpoints; @pxref{Continuing and Stepping}.) @node Conditions, Break Commands, Disabling, Breakpoints @subsection Break Conditions @@ -1998,11 +2030,11 @@ will not change the state of your other breakpoints; @c FIXME what is scope of break condition expr? Context where wanted? @c in particular for a watchpoint? -The simplest sort of breakpoint breaks every time the program reaches a +The simplest sort of breakpoint breaks every time your program reaches a specified place. You can also specify a @dfn{condition} for a breakpoint. A condition is just a Boolean expression in your -programming language. (@xref{Expressions}). A breakpoint with a condition -evaluates the expression each time the program reaches it, and the +programming language (@pxref{Expressions}). A breakpoint with a condition +evaluates the expression each time your program reaches it, and the program stops only if the condition is @emph{true}. This is the converse of using assertions for program validation; in that @@ -2017,34 +2049,34 @@ it might be simpler, say, to just set a watchpoint on a variable name, and specify a condition that tests whether the new value is an interesting one. -Break conditions ca have side effects, and may even call functions in +Break conditions can have side effects, and may even call functions in your program. This can be useful, for example, to activate functions -that log program progress, or to use your own print functions to format -special data structures. The effects are completely predictable unless -there is another enabled breakpoint at the same address. (In that -case, _GDBN__ might see the other breakpoint first and stop the program -without checking the condition of this one.) Note that breakpoint -commands are usually more convenient and flexible for the purpose of -performing side effects when a breakpoint is reached -(@pxref{Break Commands}). +that log program progress, or to use your own print functions to +format special data structures. The effects are completely predictable +unless there is another enabled breakpoint at the same address. (In +that case, _GDBN__ might see the other breakpoint first and stop your +program without checking the condition of this one.) Note that +breakpoint commands are usually more convenient and flexible for the +purpose of performing side effects when a breakpoint is reached +(@pxref{Break Commands, ,Breakpoint Command Lists}). Break conditions can be specified when a breakpoint is set, by using -@samp{if} in the arguments to the @code{break} command. @xref{Set Breaks}. -They can also be changed at any time with the @code{condition} command. -The @code{watch} command doesn't recognize the @code{if} keyword; -@code{condition} is the only way to impose a further condition on a -watchpoint. +@samp{if} in the arguments to the @code{break} command. @xref{Set +Breaks, ,Setting Breakpoints}. They can also be changed at any time +with the @code{condition} command. The @code{watch} command does not +recognize the @code{if} keyword; @code{condition} is the only way to +impose a further condition on a watchpoint. @table @code @item condition @var{bnum} @var{expression} @kindex condition Specify @var{expression} as the break condition for breakpoint or watchpoint number @var{bnum}. From now on, this breakpoint will stop -the program only if the value of @var{expression} is true (nonzero, in +your program only if the value of @var{expression} is true (nonzero, in C). When you use @code{condition}, _GDBN__ checks @var{expression} immediately for syntactic correctness, and to determine whether symbols in it have referents in the context of your breakpoint. -@c FIXME so what does GDB do if there's no referent? Moreover, what +@c FIXME so what does GDB do if there is no referent? Moreover, what @c about watchpoints? _GDBN__ does not actually evaluate @var{expression} at the time the @code{condition} @@ -2061,7 +2093,7 @@ breakpoint has been reached a certain number of times. This is so useful that there is a special way to do it, using the @dfn{ignore count} of the breakpoint. Every breakpoint has an ignore count, which is an integer. Most of the time, the ignore count is zero, and -therefore has no effect. But if the program reaches a breakpoint whose +therefore has no effect. But if your program reaches a breakpoint whose ignore count is positive, then instead of stopping, it just decrements the ignore count by one and continues. As a result, if the ignore count value is @var{n}, the breakpoint will not stop the next @var{n} times it @@ -2082,12 +2114,12 @@ a count of zero. @itemx c @var{count} @itemx fg @var{count} @kindex continue @var{count} -Continue execution of the program, setting the ignore count of the -breakpoint that the program stopped at to @var{count} minus one. -Thus, the program will not stop at this breakpoint until the +Continue execution of your program, setting the ignore count of the +breakpoint where your program stopped to @var{count} minus one. +Thus, your program will not stop at this breakpoint until the @var{count}'th time it is reached. -An argument to this command is meaningful only when the program stopped +An argument to this command is meaningful only when your program stopped due to a breakpoint. At other times, the argument to @code{continue} is ignored. @@ -2099,16 +2131,17 @@ If a breakpoint has a positive ignore count and a condition, the condition is not checked. Once the ignore count reaches zero, the condition will be checked. -You could achieve the effect of the ignore count with a -condition such as _0__@w{@samp{$foo-- <= 0}}_1__ using a debugger convenience -variable that is decremented each time. @xref{Convenience Vars}. +You could achieve the effect of the ignore count with a condition such +as _0__@w{@samp{$foo-- <= 0}}_1__ using a debugger convenience +variable that is decremented each time. @xref{Convenience Vars, +,Convenience Variables}.@refill @node Break Commands, Breakpoint Menus, Conditions, Breakpoints @subsection Breakpoint Command Lists @cindex breakpoint commands You can give any breakpoint (or watchpoint) a series of commands to -execute when the program stops due to that breakpoint. For example, you +execute when your program stops due to that breakpoint. For example, you might want to print the values of certain expressions, or enable other breakpoints. @@ -2133,7 +2166,7 @@ encountered). Pressing @key{RET} as a means of repeating the last _GDBN__ command is disabled within a @var{command-list}. -You can use breakpoint commands to start the program up again. Simply +You can use breakpoint commands to start your program up again. Simply use the @code{continue} command, or @code{step}, or any other command that resumes execution. Subsequent commands in the command list are ignored. @@ -2146,8 +2179,9 @@ If the remaining commands too print nothing, you will see no sign that the breakpoint was reached at all. @code{silent} is meaningful only at the beginning of a breakpoint command list. -The commands @code{echo} and @code{output} that allow you to print precisely -controlled output are often useful in silent breakpoints. @xref{Output}. +The commands @code{echo} and @code{output} that allow you to print +precisely controlled output are often useful in silent breakpoints. +@xref{Output, ,Commands for Controlled Output}. For example, here is how you could use breakpoint commands to print the value of @code{x} at entry to @code{foo} whenever @code{x} is positive. @@ -2168,7 +2202,7 @@ you can test for another. Put a breakpoint just after the erroneous line of code, give it a condition to detect the case in which something erroneous has been done, and give it commands to assign correct values to any variables that need them. End with the @code{continue} command -so that the program does not stop, and start with the @code{silent} +so that your program does not stop, and start with the @code{silent} command so that no output is produced. Here is an example: @example @@ -2198,10 +2232,10 @@ condition 5 (x = y + 4), 0 @end example @noindent -specifies a condition expression (@xref{Expressions}) that will change -@code{x} as needed, then always have the value zero so the program will +specifies a condition expression (@pxref{Expressions}) that will change +@code{x} as needed, then always have the value zero so your program will not stop. No input is lost here, because _GDBN__ evaluates break -conditions without changing the terminal modes. When you want to have +conditions without changing the terminal modes. When you want to have nontrivial conditions for performing the side effects, the operators @samp{&&}, @samp{||} and @samp{?@dots{}:} may be useful. @@ -2265,15 +2299,15 @@ When this happens, you have three ways to proceed: Remove or disable the breakpoints, then continue. @item -Suspend _GDBN__, and copy the file containing the program to a new name. +Suspend _GDBN__, and copy the file containing your program to a new name. Resume _GDBN__ and use the @code{exec-file} command to specify that _GDBN__ -should run the program under that name. Then start the program again. +should run your program under that name. Then start your program again. @c FIXME: RMS commented here "Show example". Maybe when someone @c explains the first FIXME: in this section... @item -Relink the program so that the text segment is nonsharable, using the +Relink your program so that the text segment is nonsharable, using the linker option @samp{-N}. The operating system limitation may not apply to nonsharable executables. @end enumerate @@ -2289,37 +2323,38 @@ completes normally. In contrast, @dfn{stepping} means executing just one more ``step'' of your program, where ``step'' may mean either one line of source code, or one machine instruction (depending on what particular command you use). Either when continuing -or when stepping, the program may stop even sooner, due to a breakpoint +or when stepping, your program may stop even sooner, due to a breakpoint or to a signal. (If due to a signal, you may want to use @code{handle}, -or use @samp{signal 0} to resume execution; @pxref{Signals}.) +or use @samp{signal 0} to resume execution. @xref{Signals}.)@refill @table @code @item continue @r{[}@var{ignore-count}@r{]} @kindex continue -Resume program execution, at the address where the program last stopped; +Resume program execution, at the address where your program last stopped; any breakpoints set at that address are bypassed. The optional argument @var{ignore-count} allows you to specify a further number of times to ignore a breakpoint at this location; its effect is like that of -@code{ignore} (@pxref{Conditions}). +@code{ignore} (@pxref{Conditions, ,Break Conditions}). To resume execution at a different place, you can use @code{return} -(@pxref{Returning}) to go back to the calling function; or @code{jump} -(@pxref{Jumping}) to go to an arbitrary location in your program. +(@pxref{Returning, ,Returning from a Function}) to go back to the +calling function; or @code{jump} (@pxref{Jumping, ,Continuing at a +Different Address}) to go to an arbitrary location in your program.@refill @end table A typical technique for using stepping is to set a breakpoint -(@pxref{Breakpoints}) at the beginning of the function or the section of -the program in which a problem is believed to lie, run the program until -it stops at that breakpoint, and then step through the suspect area, -examining the variables that are interesting, until you see the problem -happen. +(@pxref{Breakpoints, ,Breakpoints Watchpoints and Exceptions}) at the +beginning of the function or the section of your program where a +problem is believed to lie, run your program until it stops at that +breakpoint, and then step through the suspect area, examining the +variables that are interesting, until you see the problem happen. @table @code @item step @kindex step @kindex s -Continue running the program until control reaches a different source +Continue running your program until control reaches a different source line, then stop it and return control to _GDBN__. This command is abbreviated @code{s}. @@ -2355,7 +2390,8 @@ function are executed without stopping. Continue running until just after function in the selected stack frame returns. Print the returned value (if any). -Contrast this with the @code{return} command (@pxref{Returning}). +Contrast this with the @code{return} command (@pxref{Returning, +,Returning from a Function}).@refill @item until @kindex until @@ -2369,12 +2405,12 @@ automatically continues execution until the program counter is greater than the address of the jump. This means that when you reach the end of a loop after single stepping -though it, @code{until} will cause the program to continue execution +though it, @code{until} will cause your program to continue execution until the loop is exited. In contrast, a @code{next} command at the end of a loop will simply step back to the beginning of the loop, which would force you to step through the next iteration. -@code{until} always stops the program if it attempts to exit the current +@code{until} always stops your program if it attempts to exit the current stack frame. @code{until} may produce somewhat counterintuitive results if the order @@ -2405,11 +2441,11 @@ argument. @item until @var{location} @item u @var{location} -Continue running the program until either the specified location is -reached, or the current stack frame returns. @var{location} -is any of the forms of argument acceptable to @code{break} -(@pxref{Set Breaks}). This form of the command uses breakpoints, and -hence is quicker than @code{until} without an argument. +Continue running your program until either the specified location is +reached, or the current stack frame returns. @var{location} is any of +the forms of argument acceptable to @code{break} (@pxref{Set Breaks, +,Setting Breakpoints}). This form of the command uses breakpoints, +and hence is quicker than @code{until} without an argument.@refill @item stepi @itemx si @@ -2419,7 +2455,8 @@ Execute one machine instruction, then stop and return to the debugger. It is often useful to do @samp{display/i $pc} when stepping by machine instructions. This will cause the next instruction to be executed to -be displayed automatically at each stop. @xref{Auto Display}. +be displayed automatically at each stop. @xref{Auto Display, +,Automatic Display}. An argument is a repeat count, as in @code{step}. @@ -2444,25 +2481,25 @@ kind a name and a number. For example, in Unix @code{SIGINT} is the signal a program gets when you type an interrupt (often @kbd{C-c}); @code{SIGSEGV} is the signal a program gets from referencing a place in memory far away from all the areas in use; @code{SIGALRM} occurs when -the alarm clock timer goes off (which happens only if the program has +the alarm clock timer goes off (which happens only if your program has requested an alarm). @cindex fatal signals Some signals, including @code{SIGALRM}, are a normal part of the -functioning of the program. Others, such as @code{SIGSEGV}, indicate -errors; these signals are @dfn{fatal} (kill the program immediately) if the +functioning of your program. Others, such as @code{SIGSEGV}, indicate +errors; these signals are @dfn{fatal} (kill your program immediately) if the program has not specified in advance some other way to handle the signal. -@code{SIGINT} does not indicate an error in the program, but it is normally +@code{SIGINT} does not indicate an error in your program, but it is normally fatal so it can carry out the purpose of the interrupt: to kill the program. -_GDBN__ has the ability to detect any occurrence of a signal in the program -running under _GDBN__'s control. You can tell _GDBN__ in advance what to do for -each kind of signal. +_GDBN__ has the ability to detect any occurrence of a signal in your +program. You can tell _GDBN__ in advance what to do for each kind of +signal. @cindex handling signals Normally, _GDBN__ is set up to ignore non-erroneous signals like @code{SIGALRM} -(so as not to interfere with their role in the functioning of the program) -but to stop the program immediately whenever an error signal happens. +(so as not to interfere with their role in the functioning of your program) +but to stop your program immediately whenever an error signal happens. You can change these settings with the @code{handle} command. @table @code @@ -2485,11 +2522,11 @@ Their full names are: @table @code @item nostop -_GDBN__ should not stop the program when this signal happens. It may +_GDBN__ should not stop your program when this signal happens. It may still print a message telling you that the signal has come in. @item stop -_GDBN__ should stop the program when this signal happens. This implies +_GDBN__ should stop your program when this signal happens. This implies the @code{print} keyword as well. @item print @@ -2500,30 +2537,31 @@ _GDBN__ should not mention the occurrence of the signal at all. This implies the @code{nostop} keyword as well. @item pass -_GDBN__ should allow the program to see this signal; the program will be +_GDBN__ should allow your program to see this signal; your program will be able to handle the signal, or may be terminated if the signal is fatal and not handled. @item nopass -_GDBN__ should not allow the program to see this signal. +_GDBN__ should not allow your program to see this signal. @end table @c @end group -When a signal has been set to stop the program, the program cannot see the +When a signal has been set to stop your program, your program cannot see the signal until you continue. It will see the signal then, if @code{pass} is in effect for the signal in question @i{at that time}. In other words, after _GDBN__ reports a signal, you can use the @code{handle} command with @code{pass} or @code{nopass} to control whether that signal will be seen by -the program when you later continue it. +your program when you later continue it. -You can also use the @code{signal} command to prevent the program from +You can also use the @code{signal} command to prevent your program from seeing a signal, or cause it to see a signal it normally would not see, -or to give it any signal at any time. For example, if the program stopped +or to give it any signal at any time. For example, if your program stopped due to some sort of memory reference error, you might store correct values into the erroneous variables and continue, hoping to see more -execution; but the program would probably terminate immediately as -a result of the fatal signal once it sees the signal. To prevent this, -you can continue with @samp{signal 0}. @xref{Signaling}. +execution; but your program would probably terminate immediately as +a result of the fatal signal once it saw the signal. To prevent this, +you can continue with @samp{signal 0}. @xref{Signaling, ,Giving your +Program a Signal}. @node Stack, Source, Stopping, Top @chapter Examining the Stack @@ -2533,7 +2571,7 @@ stopped and how it got there. @cindex call stack Each time your program performs a function call, the information about -where in the program the call was made from is saved in a block of data +where in your program the call was made from is saved in a block of data called a @dfn{stack frame}. The frame also contains the arguments of the call and the local variables of the function that was called. All the stack frames are allocated in a region of memory called the @dfn{call @@ -2545,13 +2583,13 @@ to see all of this information. @cindex selected frame One of the stack frames is @dfn{selected} by _GDBN__ and many _GDBN__ commands refer implicitly to the selected frame. In particular, whenever you ask -_GDBN__ for the value of a variable in the program, the value is found in the +_GDBN__ for the value of a variable in your program, the value is found in the selected frame. There are special _GDBN__ commands to select whichever frame you are interested in. -When the program stops, _GDBN__ automatically selects the currently executing +When your program stops, _GDBN__ automatically selects the currently executing frame and describes it briefly as the @code{frame} command does -(@pxref{Frame Info}). +(@pxref{Frame Info, ,Information About a Frame}). @menu * Frames:: Stack Frames @@ -2613,7 +2651,7 @@ for frameless functions elsewhere in the stack. @node Backtrace, Selection, Frames, Stack @section Backtraces -A backtrace is a summary of how the program got where it is. It shows one +A backtrace is a summary of how your program got where it is. It shows one line per frame, for many frames, starting with the currently executing frame (frame zero), followed by its caller (frame one), and on up the stack. @@ -2666,14 +2704,14 @@ Here is an example of a backtrace. It was made with the command @end smallexample @noindent -The display for frame zero doesn't begin with a program counter -value, indicating that the program has stopped at the beginning of the +The display for frame zero does not begin with a program counter +value, indicating that your program has stopped at the beginning of the code for line @code{993} of @code{builtin.c}. @node Selection, Frame Info, Backtrace, Stack @section Selecting a Frame -Most commands for examining the stack and other data in the program work on +Most commands for examining the stack and other data in your program work on whichever stack frame is selected at the moment. Here are the commands for selecting a stack frame; all of them finish by printing a brief description of the stack frame just selected. @@ -2693,7 +2731,7 @@ frame. Select the frame at address @var{addr}. This is useful mainly if the chaining of stack frames has been damaged by a bug, making it impossible for _GDBN__ to assign numbers properly to all frames. In -addition, this can be useful when the program has multiple stacks and +addition, this can be useful when your program has multiple stacks and switches between them. _if__(_SPARC__) @@ -2727,14 +2765,17 @@ frame. The second line shows the text of that source line. For example: @smallexample +@group (_GDBP__) up #1 0x22f0 in main (argc=1, argv=0xf7fffbf4, env=0xf7fffbfc) at env.c:10 10 read_input_file (argv[i]); +@end group @end smallexample -After such a printout, the @code{list} command with no arguments will print -ten lines centered on the point of execution in the frame. @xref{List}. +After such a printout, the @code{list} command with no arguments will +print ten lines centered on the point of execution in the frame. +@xref{List, ,Printing Source Lines}. @table @code @item up-silently @var{n} @@ -2758,14 +2799,15 @@ stack frame. @table @code @item frame @itemx f -When used without any argument, this command does not change which frame -is selected, but prints a brief description of the currently +When used without any argument, this command does not change which +frame is selected, but prints a brief description of the currently selected stack frame. It can be abbreviated @code{f}. With an -argument, this command is used to select a stack frame (@pxref{Selection}). +argument, this command is used to select a stack frame +(@pxref{Selection, ,Selecting a Frame}). @item info frame -@kindex info frame @itemx info f +@kindex info frame @kindex info f This command prints a verbose description of the selected stack frame, including the address of the frame, the addresses of the next frame down @@ -2801,7 +2843,7 @@ Print a list of all the exception handlers that are active in the current stack frame at the current point of execution. To see other exception handlers, visit the associated frame (using the @code{up}, @code{down}, or @code{frame} commands); then type @code{info catch}. -@xref{Exception Handling}. +@xref{Exception Handling, ,Breakpoints and Exceptions}.@refill @end table @node Source, Data, Stack, Top @@ -2809,14 +2851,15 @@ exception handlers, visit the associated frame (using the @code{up}, _GDBN__ can print parts of your program's source, since the debugging information recorded in your program tells _GDBN__ what source files -were used to built it. When your program stops, _GDBN__ spontaneously +were used to build it. When your program stops, _GDBN__ spontaneously prints the line where it stopped. Likewise, when you select a stack -frame (@pxref{Selection}), _GDBN__ prints the line where execution in -that frame has stopped. You can print other portions of source files by -explicit command. +frame (@pxref{Selection, ,Selecting a Frame}), _GDBN__ prints the line +where execution in that frame has stopped. You can print other +portions of source files by explicit command.@refill If you use _GDBN__ through its GNU Emacs interface, you may prefer to -use Emacs facilities to view source; @pxref{Emacs}. +use Emacs facilities to view source; @pxref{Emacs, ,Using _GDBN__ +under GNU Emacs}.@refill @menu * List:: Printing Source Lines @@ -2849,8 +2892,8 @@ Print lines centered around the beginning of function Print more lines. If the last lines printed were printed with a @code{list} command, this prints lines following the last lines printed; however, if the last line printed was a solitary line printed -as part of displaying a stack frame (@pxref{Stack}), this prints -lines centered around that line. +as part of displaying a stack frame (@pxref{Stack, ,Examining the +Stack}), this prints lines centered around that line.@refill @item list - Print lines just before the lines last printed. @@ -2985,7 +3028,7 @@ the executable search path is @emph{not} used for this purpose. Neither is the current working directory, unless it happens to be in the source path. -If _GDBN__ can't find a source file in the source path, and the object +If _GDBN__ cannot find a source file in the source path, and the object program records a directory, _GDBN__ tries that directory too. If the source path is empty, and there is no record of the compilation directory, _GDBN__ will, as a last resort, look in the current @@ -3017,7 +3060,7 @@ directory at the time you add an entry to the source path. Reset the source path to empty again. This requires confirmation. @c RET-repeat for @code{directory} is explicitly disabled, but since -@c repeating it would be a no-op we don't say that. (thanks to RMS) +@c repeating it would be a no-op we do not say that. (thanks to RMS) @item show directories @kindex show directories @@ -3049,7 +3092,7 @@ a range of addresses as machine instructions. @kindex info line Print the starting and ending addresses of the compiled code for source line @var{linespec}. You can specify source lines in any of the -ways understood by the @code{list} command (@pxref{List}). +ways understood by the @code{list} command (@pxref{List, ,Printing Source Lines}). @end table For example, we can use @code{info line} to inquire on where the object @@ -3068,11 +3111,12 @@ Line 926 of "builtin.c" starts at pc 0x63e4 and ends at 0x6404. @end smallexample @cindex @code{$_} and @code{info line} -After @code{info line}, the default address for the @code{x} -command is changed to the starting address of the line, so that -@samp{x/i} is sufficient to begin examining the machine code -(@pxref{Memory}). Also, this address is saved as the value of the -convenience variable @code{$_} (@pxref{Convenience Vars}). +After @code{info line}, the default address for the @code{x} command +is changed to the starting address of the line, so that @samp{x/i} is +sufficient to begin examining the machine code (@pxref{Memory, +,Examining Memory}). Also, this address is saved as the value of the +convenience variable @code{$_} (@pxref{Convenience Vars, ,Convenience +Variables}). @table @code @kindex disassemble @@ -3112,8 +3156,8 @@ End of assembler dump. @cindex examining data @kindex print @kindex inspect -@c "inspect" isn't quite a synonym if you're using Epoch, which we don't -@c document because it's nonstandard... Under Epoch it displays in a +@c "inspect" isn't quite a synonym if you are using Epoch, which we do not +@c document because it is nonstandard... Under Epoch it displays in a @c different window or something like that. The usual way to examine data in your program is with the @code{print} command (abbreviated @code{p}), or its synonym @code{inspect}. It @@ -3137,9 +3181,9 @@ conveniently inspect the same value in an alternative format. A more low-level way of examining data is with the @code{x} command. It examines data in memory at a specified address and prints it in a -specified format. @xref{Memory}. +specified format. @xref{Memory, ,Examining Memory}. -If you're interested in information about types, or about how the fields +If you are interested in information about types, or about how the fields of a struct or class are declared, use the @code{ptype @var{exp}} command rather than @code{print}. @xref{Symbols}. @@ -3208,9 +3252,10 @@ The most common kind of expression to use is the name of a variable in your program. Variables in expressions are understood in the selected stack frame -(@pxref{Selection}); they must either be global (or static) or be visible -according to the scope rules of the programming language from the point of -execution in that frame. This means that in the function +(@pxref{Selection, ,Selecting a Frame}); they must either be global +(or static) or be visible according to the scope rules of the +programming language from the point of execution in that frame. This +means that in the function @example foo (a) @@ -3225,9 +3270,9 @@ foo (a) @end example @noindent -the variable @code{a} is usable whenever the program is executing +the variable @code{a} is usable whenever your program is executing within the function @code{foo}, but the variable @code{b} is visible -only while the program is executing inside the block in which @code{b} +only while your program is executing inside the block in which @code{b} is declared. @cindex variable name conflict @@ -3240,7 +3285,7 @@ specify a variable in a particular file, using the colon-colon notation: @cindex colon-colon @iftex -@c info can't cope with a :: index entry, but why deprive hard copy readers? +@c info cannot cope with a :: index entry, but why deprive hard copy readers? @kindex :: @end iftex @example @@ -3260,10 +3305,10 @@ scope resolution operator in _GDBN__ expressions. @quotation @emph{Warning:} Occasionally, a local variable may appear to have the wrong value at certain points in a function---just after entry to the -function, and just before exit. You may see this problem when you're +function, and just before exit. You may see this problem when you are stepping by machine instructions. This is because on most machines, it takes more than one instruction to set up a stack frame (including local -variable definitions); if you're stepping by machine instructions, +variable definitions); if you are stepping by machine instructions, variables may appear to have the wrong values until the stack frame is completely built. On function exit, it usually also takes more than one machine instruction to destroy a stack frame; after you begin stepping @@ -3309,14 +3354,15 @@ Artificial arrays most often appear in expressions via the value history Sometimes the artificial array mechanism isn't quite enough; in moderately complex data structures, the elements of interest may not -actually be adjacent---for example, if you're interested in the values -of pointers in an array. One useful work-around in this situation is to -use a convenience variable (@pxref{Convenience Vars}) as a counter in an -expression that prints the first interesting value, and then repeat that -expression via @key{RET}. For instance, suppose you have an array -@code{dtab} of pointers to structures, and you're interested in the -values of a field @code{fv} in each structure. Here's an example of -what you might type: +actually be adjacent---for example, if you are interested in the +values of pointers in an array. One useful work-around in this +situation is to use a convenience variable (@pxref{Convenience Vars, +,Convenience Variables}) as a counter in an expression that prints the +first interesting value, and then repeat that expression via +@key{RET}. For instance, suppose you have an array @code{dtab} of +pointers to structures, and you are interested in the values of a +field @code{fv} in each structure. Here's an example of what you +might type: @example set $i = 0 p dtab[$i++]->fv @@ -3452,7 +3498,7 @@ words (@samp{w}) of memory above the stack pointer (here, @samp{$sp}; @pxref{Registers}) in hexadecimal (@samp{x}). Since the letters indicating unit sizes are all distinct from the -letters specifying output formats, you don't have to remember whether +letters specifying output formats, you do not have to remember whether unit size or format comes first; either order will work. The output specifications @samp{4xw} and @samp{4wx} mean exactly the same thing. (However, the count @var{n} must come first; @samp{wx4} will not work.) @@ -3493,7 +3539,7 @@ address printed if several units were printed on the last line of output. If you find that you want to print the value of an expression frequently (to see how it changes), you might want to add it to the @dfn{automatic -display list} so that _GDBN__ will print its value each time the program stops. +display list} so that _GDBN__ will print its value each time your program stops. Each expression added to the list is given a number to identify it; to remove an expression from the list, you specify that number. The automatic display looks like this: @@ -3516,7 +3562,7 @@ supported by @code{x}; otherwise it uses @code{print}. @item display @var{exp} @kindex display Add the expression @var{exp} to the list of expressions to display -each time the program stops. @xref{Expressions}. +each time your program stops. @xref{Expressions}. @code{display} will not repeat if you press @key{RET} again after using it. @@ -3529,8 +3575,8 @@ arranges to display it each time in the specified format @var{fmt}. @item display/@var{fmt} @var{addr} For @var{fmt} @samp{i} or @samp{s}, or including a unit-size or a number of units, add the expression @var{addr} as a memory address to -be examined each time the program stops. Examining means in effect -doing @samp{x/@var{fmt} @var{addr}}. @xref{Memory}. +be examined each time your program stops. Examining means in effect +doing @samp{x/@var{fmt} @var{addr}}. @xref{Memory, ,Examining Memory}. @end table For example, @samp{display/i $pc} can be helpful, to see the machine @@ -3560,7 +3606,7 @@ again in auto display of its expression, until you specify otherwise. @item display Display the current values of the expressions on the list, just as is -done when the program stops. +done when your program stops. @item info display @kindex info display @@ -3576,7 +3622,7 @@ sense outside the lexical context for which it was set up. Such an expression is disabled when execution enters a context where one of its variables is not defined. For example, if you give the command @code{display last_char} while inside a function with an argument -@code{last_char}, then this argument will be displayed while the program +@code{last_char}, then this argument will be displayed while your program continues to stop inside that function. When it stops elsewhere---where there is no variable @code{last_char}---display is disabled. The next time your program stops where @code{last_char} is meaningful, you can enable the @@ -3932,11 +3978,12 @@ values likely to be useful. @item $_ @kindex $_ The variable @code{$_} is automatically set by the @code{x} command to -the last address examined (@pxref{Memory}). Other commands which -provide a default address for @code{x} to examine also set @code{$_} -to that address; these commands include @code{info line} and @code{info -breakpoint}. The type of @code{$_} is @code{void *} except when set by the -@code{x} command, in which case it is a pointer to the type of @code{$__}. +the last address examined (@pxref{Memory, ,Examining Memory}). Other +commands which provide a default address for @code{x} to examine also +set @code{$_} to that address; these commands include @code{info line} +and @code{info breakpoint}. The type of @code{$_} is @code{void *} +except when set by the @code{x} command, in which case it is a pointer +to the type of @code{$__}. @item $__ @kindex $__ @@ -3973,7 +4020,7 @@ or without the initial @samp{$}. @end table _GDBN__ has four ``standard'' register names that are available (in -expressions) on most machines---whenever they don't conflict with an +expressions) on most machines---whenever they do not conflict with an architecture's canonical mnemonics for registers. The register names @code{$pc} and @code{$sp} are used for the program counter register and the stack pointer. @code{$fp} is used for a register that contains a @@ -3991,12 +4038,13 @@ x/i $pc @end example @noindent -or add four to the stack pointer @footnote{This is a way of removing one -word from the stack, on machines where stacks grow downward in memory -(most machines, nowadays). This assumes that the innermost stack frame -is selected; setting @code{$sp} is not allowed when other stack frames -are selected. To pop entire frames off the stack, regardless of -machine architecture, use @code{return}; @pxref{Returning}.} with +or add four to the stack pointer @footnote{This is a way of removing +one word from the stack, on machines where stacks grow downward in +memory (most machines, nowadays). This assumes that the innermost +stack frame is selected; setting @code{$sp} is not allowed when other +stack frames are selected. To pop entire frames off the stack, +regardless of machine architecture, use @code{return}; +@pxref{Returning, ,Returning from a Function}.} with@refill @example set $sp += 4 @end example @@ -4027,11 +4075,11 @@ makes sense for your program), but the @code{info registers} command prints the data in both formats. Normally, register values are relative to the selected stack frame -(@pxref{Selection}). This means that you get the value that the -register would contain if all stack frames farther in were exited and -their saved registers restored. In order to see the true contents of -hardware registers, you must select the innermost frame (with -@samp{frame 0}). +(@pxref{Selection, ,Selecting a Frame}). This means that you get the +value that the register would contain if all stack frames farther in +were exited and their saved registers restored. In order to see the +true contents of hardware registers, you must select the innermost +frame (with @samp{frame 0}). However, _GDBN__ must deduce where registers are saved, from the machine code generated by your compiler. If some registers are not saved, or if @@ -4069,9 +4117,9 @@ like @samp{0x1ae}, while in Modula-2 they appear as @samp{1AEH}. @cindex working language Language-specific information is built into _GDBN__ for some languages, -allowing you to express operations like the above in the program's +allowing you to express operations like the above in your program's native language, and allowing _GDBN__ to output values in a manner -consistent with the syntax of the program's native language. The +consistent with the syntax of your program's native language. The language you use to build expressions, called the @dfn{working language}, can be selected manually, or _GDBN__ can set it automatically. @@ -4170,7 +4218,7 @@ working language, and also what language source files were written in. @item show language Display the current working language. This is the language you can use with commands such as @code{print} to -build and compute expressions that may involve variables in the program. +build and compute expressions that may involve variables in your program. @item info frame Among the other information listed here (@pxref{Frame Info,,Information @@ -4200,16 +4248,15 @@ checking the type of arguments to functions and operators, and making sure mathematical overflows are caught at run time. Checks such as these help to ensure a program's correctness once it has been compiled by eliminating type mismatches, and providing active checks for range -errors when the program is running. +errors when your program is running. -_GDBN__ can check for conditions like the above if you wish. -Although _GDBN__ will not check the statements in your program, it -can check expressions entered directly into _GDBN__ for evaluation via -the @code{print} command, for example. As with the working language, +_GDBN__ can check for conditions like the above if you wish. Although +_GDBN__ will not check the statements in your program, it can check +expressions entered directly into _GDBN__ for evaluation via the +@code{print} command, for example. As with the working language, _GDBN__ can also decide whether or not to check automatically based on -the source language of the program being debugged. -@xref{Support,,Supported Languages}, for the default settings -of supported languages. +your program's source language. @xref{Support,,Supported Languages}, +for the default settings of supported languages.@refill @menu * Type Checking:: An overview of type checking @@ -4723,12 +4770,13 @@ you want. @xref{Breakpoint Menus}. Setting breakpoints using regular expressions is helpful for setting breakpoints on overloaded functions that are not members of any special classes. -@xref{Set Breaks}. +@xref{Set Breaks, ,Setting Breakpoints}. @cindex C++ exception handling @item catch @var{exceptions} @itemx info catch -Debug C++ exception handling using these commands. @xref{Exception Handling}. +Debug C++ exception handling using these commands. @xref{Exception +Handling, ,Breakpoints and Exceptions}. @refill @cindex inheritance @item ptype @var{typename} @@ -4771,7 +4819,7 @@ as _GDBN__ reads in the executable's symbol table. @cindex expressions in Modula-2 @menu * M2 Operators:: Built-in operators -* Builtin Func/Proc:: Built-in Functions and Procedures +* Built-In Func/Proc:: Built-in Functions and Procedures * M2 Constants:: Modula-2 Constants * M2 Defaults:: Default settings for Modula-2 * Deviations:: Deviations from standard Modula-2 @@ -4780,7 +4828,7 @@ as _GDBN__ reads in the executable's symbol table. * GDB/M2:: _GDBN__ and Modula-2 @end menu -@node M2 Operators, Builtin Func/Proc, Modula-2, Modula-2 +@node M2 Operators, Built-In Func/Proc, Modula-2, Modula-2 @subsubsection Operators @cindex Modula-2 operators @@ -4907,8 +4955,8 @@ will treat the use of the operator @code{IN}, or the use of operators @end quotation _1__ -@cindex Modula-2 builtins -@node Builtin Func/Proc, M2 Constants, M2 Operators, Modula-2 +@cindex Modula-2 built-ins +@node Built-In Func/Proc, M2 Constants, M2 Operators, Modula-2 @subsubsection Built-in Functions and Procedures Modula-2 also makes available several built-in procedures and functions. @@ -5021,7 +5069,7 @@ an error. @end quotation @cindex Modula-2 constants -@node M2 Constants, M2 Defaults, Builtin Func/Proc, Modula-2 +@node M2 Constants, M2 Defaults, Built-In Func/Proc, Modula-2 @subsubsection Constants _GDBN__ allows you to express the constants of Modula-2 in the following @@ -5111,7 +5159,7 @@ The assignment operator (@code{:=}) returns the value of its right-hand argument. @item -All builtin procedures both modify @emph{and} return their argument. +All built-in procedures both modify @emph{and} return their argument. @end itemize @@ -5142,7 +5190,7 @@ As long as type checking is enabled, any attempt to combine variables whose types are not equivalent is an error. Range checking is done on all mathematical operations, assignment, array -index bounds, and all builtin functions and procedures. +index bounds, and all built-in functions and procedures. @node M2 Scope, GDB/M2, M2 Checks, Modula-2 @subsubsection The scope operators @code{::} and @code{.} @@ -5163,8 +5211,8 @@ similar syntax: @noindent where @var{scope} is the name of a module or a procedure, -@var{module} the name of a module, and @var{id} is any delcared -identifier within the program, except another module. +@var{module} the name of a module, and @var{id} is any declared +identifier within your program, except another module. Using the @code{::} operator makes _GDBN__ search the scope specified by @var{scope} for the identifier @var{id}. If it is not @@ -5208,10 +5256,10 @@ _1__ The commands described in this section allow you to inquire about the symbols (names of variables, functions and types) defined in your program. This information is inherent in the text of your program and -does not change as the program executes. _GDBN__ finds it in your +does not change as your program executes. _GDBN__ finds it in your program's symbol table, in the file indicated when you started _GDBN__ (@pxref{File Options}), or by one of the file-management commands -(@pxref{Files}). +(@pxref{Files, ,Commands to Specify Files}). @table @code @item info address @var{symbol} @@ -5288,7 +5336,7 @@ it was written in. @item info sources @kindex info sources -Print the names of all source files in the program for which there is +Print the names of all source files in your program for which there is debugging information, organized into two lists: files whose symbols have already been read, and files whose symbols will be read when needed. @@ -5345,27 +5393,27 @@ sources} to find out which files these are. If you use _GDBN__ only knows partially---that is, symbols defined in files that _GDBN__ has skimmed, but not yet read completely. The description of @code{symbol-file} describes how _GDBN__ reads symbols; both commands -are described under @ref{Files}. +are described under @ref{Files, ,Commands to Specify Files}. @end table @node Altering, _GDBN__ Files, Symbols, Top @chapter Altering Execution -Once you think you have found an error in the program, you might want to +Once you think you have found an error in your program, you might want to find out for certain whether correcting the apparent error would lead to correct results in the rest of the run. You can find the answer by experiment, using the _GDBN__ features for altering execution of the program. For example, you can store new values into variables or memory -locations, give the program a signal, restart it at a different address, +locations, give your program a signal, restart it at a different address, or even return prematurely from a function to its caller. @menu * Assignment:: Assignment to Variables * Jumping:: Continuing at a Different Address -* Signaling:: Giving the Program a Signal +* Signaling:: Giving your program a Signal * Returning:: Returning from a Function * Calling:: Calling your Program's Functions * Patching:: Patching your Program @@ -5441,7 +5489,7 @@ stores the value 4 into that memory location. @node Jumping, Signaling, Assignment, Altering @section Continuing at a Different Address -Ordinarily, when you continue the program, you do so at the place where +Ordinarily, when you continue your program, you do so at the place where it stopped, with the @code{continue} command. You can instead continue at an address of your own choosing, with the following commands: @@ -5449,8 +5497,9 @@ an address of your own choosing, with the following commands: @item jump @var{linespec} @kindex jump Resume execution at line @var{linespec}. Execution will stop -immediately if there is a breakpoint there. @xref{List} for a -description of the different forms of @var{linespec}. +immediately if there is a breakpoint there. @xref{List, ,Printing +Source Lines}, for a description of the different forms of +@var{linespec}. The @code{jump} command does not change the current stack frame, or the stack pointer, or the contents of any memory location or any @@ -5460,7 +5509,7 @@ be bizarre if the two functions expect different patterns of arguments or of local variables. For this reason, the @code{jump} command requests confirmation if the specified line is not in the function currently executing. However, even bizarre results are predictable if you are -well acquainted with the machine-language code of the program. +well acquainted with the machine-language code of your program. @item jump *@var{address} Resume execution at the instruction at address @var{address}. @@ -5468,7 +5517,7 @@ Resume execution at the instruction at address @var{address}. You can get much the same effect as the @code{jump} command by storing a new value into the register @code{$pc}. The difference is that this -does not start the program running; it only changes the address where it +does not start your program running; it only changes the address where it @emph{will} run when it is continued. For example, @example @@ -5477,7 +5526,7 @@ set $pc = 0x485 @noindent causes the next @code{continue} command or stepping command to execute at -address 0x485, rather than at the address where the program stopped. +address 0x485, rather than at the address where your program stopped. @xref{Continuing and Stepping}. The most common occasion to use the @code{jump} command is to back up, @@ -5486,16 +5535,16 @@ already executed, in order to examine its execution in more detail. @node Signaling, Returning, Jumping, Altering @c @group -@section Giving the Program a Signal +@section Giving your program a Signal @table @code @item signal @var{signalnum} @kindex signal -Resume execution where the program stopped, but give it immediately the +Resume execution where your program stopped, but give it immediately the signal number @var{signalnum}. Alternatively, if @var{signalnum} is zero, continue execution without -giving a signal. This is useful when the program stopped on account of +giving a signal. This is useful when your program stopped on account of a signal and would ordinary see the signal when resumed with the @code{continue} command; @samp{signal 0} causes it to resume without a signal. @@ -5524,10 +5573,11 @@ When you use @code{return}, _GDBN__ discards the selected stack frame discarded frame return prematurely. If you wish to specify a value to be returned, give that value as the argument to @code{return}. -This pops the selected stack frame (@pxref{Selection}), and any other -frames inside of it, leaving its caller as the innermost remaining -frame. That frame becomes selected. The specified value is stored in -the registers used for returning values of functions. +This pops the selected stack frame (@pxref{Selection, ,Selecting a +Frame}), and any other frames inside of it, leaving its caller as the +innermost remaining frame. That frame becomes selected. The +specified value is stored in the registers used for returning values +of functions. The @code{return} command does not resume execution; it leaves the program stopped in the state that would exist if the function had just @@ -5598,13 +5648,13 @@ writing as well as reading. @cindex core dump file @cindex symbol table _GDBN__ needs to know the file name of the program to be debugged, both in -order to read its symbol table and in order to start the program. To +order to read its symbol table and in order to start your program. To debug a core dump of a previous run, _GDBN__ must be told the file name of the core dump. The usual way to specify the executable and core dump file names is with the command arguments given when you start _GDBN__, as discussed in -@pxref{Invocation}. +@pxref{Invocation, ,Getting In and Out of _GDBN__}. Occasionally it is necessary to change to a different file during a _GDBN__ session. Or you may run _GDBN__ and forget to specify the files you @@ -5633,7 +5683,7 @@ has on both executable file and the symbol table. @kindex exec-file Specify that the program to be run (but not the symbol table) is found in @var{filename}. _GDBN__ will search the environment variable @code{PATH} -if necessary to locate the program. Omitting @var{filename} means to +if necessary to locate your program. Omitting @var{filename} means to discard information on the executable file. @item symbol-file @r{[} @var{filename} @r{]} @@ -5664,7 +5714,8 @@ The purpose of this two-stage reading strategy is to make _GDBN__ start up faster. For the most part, it is invisible except for occasional pauses while the symbol table details for a particular source file are being read. (The @code{set verbose} command can turn these pauses into -messages if desired. @xref{Messages/Warnings}). +messages if desired. @xref{Messages/Warnings, ,Optional Warnings and +Messages}.) When the symbol table is stored in COFF format, @code{symbol-file} does read the symbol table data in full right away. We haven't implemented @@ -5689,7 +5740,7 @@ executable file itself for other parts. to be used. Note that the core file is ignored when your program is actually running -under _GDBN__. So, if you have been running the program and you wish to +under _GDBN__. So, if you have been running your program and you wish to debug a core file instead, you must kill the subprocess in which the program is running. To do this, use the @code{kill} command (@pxref{Kill Process}). @@ -5762,7 +5813,7 @@ _GDBN__ supports the SunOS shared library format. _GDBN__ automatically loads symbol definitions from shared libraries when you use the @code{run} command, or when you examine a core file. (Before you issue the @code{run} command, _GDBN__ won't understand references to a -function in a shared library, however---unless you're debugging a core +function in a shared library, however---unless you are debugging a core file). @c FIXME: next _GDBN__ release should permit some refs to undef @c FIXME...symbols---eg in a break cmd---assuming they're from a shared lib @@ -5797,7 +5848,7 @@ about ill-constructed symbol tables, you can either ask _GDBN__ to print only one message about each such type of problem, no matter how many times the problem occurs; or you can ask _GDBN__ to print more messages, to see how many times the problems occur, with the @code{set complaints} -command (@xref{Messages/Warnings}). +command (@pxref{Messages/Warnings, ,Optional Warnings and Messages}). The messages currently printed, and their meanings, are: @@ -5823,7 +5874,7 @@ do so. _GDBN__ does not circumvent this problem, and will have trouble locating symbols in the source file whose symbols being read. (You can often determine what source file is affected by specifying @code{set verbose -on}. @xref{Messages/Warnings}.) +on}. @xref{Messages/Warnings, ,Optional Warnings and Messages}.) @item bad block start address patched @@ -5851,7 +5902,7 @@ know how to read. @code{0x@var{nn}} is the symbol type of the misunderstood information, in hexadecimal. _GDBN__ circumvents the error by ignoring this symbol information. This -will usually allow the program to be debugged, though certain symbols +will usually allow your program to be debugged, though certain symbols will not be accessible. If you encounter such a problem and feel like debugging it, you can debug @code{_GDBP__} with itself, breakpoint on @code{complain}, then go up to the function @code{read_dbx_symtab} and @@ -5877,7 +5928,7 @@ _GDBN__ could not parse a type specification output by the compiler. @cindex debugging target @kindex target A @dfn{target} is the execution environment occupied by your program. -Often, _GDBN__ runs in the same host environment as the program you are +Often, _GDBN__ runs in the same host environment as your program you are debugging; in that case, the debugging target is specified as a side effect when you use the @code{file} or @code{core} commands. When you need more flexibility---for example, running _GDBN__ on a physically @@ -5910,7 +5961,7 @@ well---presumably from a prior run that crashed and coredumped---then _GDBN__ has two active targets and will use them in tandem, looking first in the corefile target, then in the executable file, to satisfy requests for memory addresses. (Typically, these two classes of target -are complementary, since core files contain only the program's +are complementary, since core files contain only a program's read-write memory---variables and so on---plus machine status, while executable files contain only the program text and initialized data.) @@ -5921,9 +5972,9 @@ core file or executable file target are obscured while the process target is active. Use the @code{core-file}, and @code{exec-file} commands to select a new -core file or executable target (@pxref{Files}). To specify as a target +core file or executable target (@pxref{Files, ,Commands to Specify Files}). To specify as a target a process that's already running, use the @code{attach} command -(@pxref{Attach}). +(@pxref{Attach, ,Debugging an Already-Running Process}.). @node Target Commands, Remote, Active Targets, Targets @section Commands for Managing Targets @@ -5946,7 +5997,7 @@ after executing the command. @kindex help target Displays the names of all targets available. To display targets currently selected, use either @code{info target} or @code{info files} -(@pxref{Files}). +(@pxref{Files, ,Commands to Specify Files}). @item help target @var{name} Describe a particular target, including any parameters necessary to @@ -6016,7 +6067,7 @@ _include__(gdbinv-m.m4)<>_dnl__ @end menu _fi__(_GENERIC__) -If you are trying to debug a program running on a machine that can't run +If you are trying to debug a program running on a machine that cannot run _GDBN__ in the usual way, it is often useful to use remote debugging. For example, you might use remote debugging on an operating system kernel, or on a small system which does not have a general purpose operating system @@ -6040,7 +6091,7 @@ _GDBN__ source file @file{remote.c}. To start remote debugging, first run _GDBN__ and specify as an executable file the program that is running in the remote machine. This tells _GDBN__ how -to find the program's symbols and the contents of its pure text. Then +to find your program's symbols and the contents of its pure text. Then establish communication using the @code{target remote} command with a device name as an argument. For example: @@ -6168,7 +6219,7 @@ This defaults to the value of the environment variable @cindex history expansion History expansion assigns special meaning to the character @kbd{!}. @iftex -(@xref{Event Designators}.) +(@pxref{Event Designators}.) @end iftex Since @kbd{!} is also the logical not operator in C, history expansion is off by default. If you decide to enable history expansion with the @@ -6305,13 +6356,13 @@ you won't think it has crashed. Currently, the messages controlled by @code{set verbose} are those which announce that the symbol table for a source file is being read -(@pxref{Files}, in the description of the command +(@pxref{Files, ,Commands to Specify Files}, in the description of the command @code{symbol-file}). -@c The following is the right way to do it, but emacs 18.55 doesn't support +@c The following is the right way to do it, but emacs 18.55 does not support @c @ref, and neither the emacs lisp manual version of texinfmt or makeinfo @c is released. @ignore -see @code{symbol-file} in @ref{Files}). +see @code{symbol-file} in @ref{Files, ,Commands to Specify Files}). @end ignore @table @code @@ -6353,7 +6404,7 @@ The program being debugged has been started already. Start it from the beginning? (y or n) @end example -If you're willing to unflinchingly face the consequences of your own +If you are willing to unflinchingly face the consequences of your own commands, you can disable this ``feature'': @table @code @@ -6372,7 +6423,7 @@ Enables confirmation requests (the default). Displays state of confirmation requests. @end table -@c FIXME this doesn't really belong here. But where *does* it belong? +@c FIXME this does not really belong here. But where *does* it belong? @cindex reloading symbols Some systems allow individual object files that make up your program to be replaced without stopping and restarting your program. @@ -6380,7 +6431,7 @@ _if__(_VXWORKS__) For example, in VxWorks you can simply recompile a defective object file and keep on running. _fi__(_VXWORKS__) -If you're running on one of these systems, you can allow _GDBN__ to +If you are running on one of these systems, you can allow _GDBN__ to reload the symbols for automatically relinked modules:@refill @table @code @kindex set symbol-reloading @@ -6389,8 +6440,8 @@ Replace symbol definitions for the corresponding source file when an object file with a particular name is seen again. @item set symbol-reloading off -Don't replace symbol definitions when re-encountering object files of -the same name. This is the default state; if you're not running on a +Do Not replace symbol definitions when re-encountering object files of +the same name. This is the default state; if you are not running on a system that permits automatically relinking modules, you should leave @code{symbol-reloading} off, since otherwise _GDBN__ may discard symbols when linking large programs, that may contain several modules (from @@ -6403,9 +6454,10 @@ Show the current @code{on} or @code{off} setting. @node Sequences, Emacs, Controlling _GDBN__, Top @chapter Canned Sequences of Commands -Aside from breakpoint commands (@pxref{Break Commands}), _GDBN__ provides two -ways to store sequences of commands for execution as a unit: -user-defined commands and command files. +Aside from breakpoint commands (@pxref{Break Commands, ,Breakpoint +Command Lists}), _GDBN__ provides two ways to store sequences of +commands for execution as a unit: user-defined commands and command +files.@refill @menu * Define:: User-Defined Commands @@ -6512,8 +6564,8 @@ want. @table @code @item echo @var{text} @kindex echo -@c I don't consider backslash-space a standard C escape sequence -@c because it's not in ANSI. +@c I do not consider backslash-space a standard C escape sequence +@c because it is not in ANSI. Print @var{text}. Nonprinting characters can be included in @var{text} using C escape sequences, such as @samp{\n} to print a newline. @b{No newline will be printed unless you specify one.} In addition to the @@ -6558,7 +6610,7 @@ information. Print the values of the @var{expressions} under the control of @var{string}. The @var{expressions} are separated by commas and may be either numbers or pointers. Their values are printed as specified -by @var{string}, exactly as if the program were to execute +by @var{string}, exactly as if your program were to execute @example printf (@var{string}, @var{expressions}@dots{}); @@ -6628,7 +6680,7 @@ current directory, it can be easy to confuse Emacs about the location of the source files, in which case the auxiliary display buffer will not appear to show your source. _GDBN__ can find programs by searching your environment's @code{PATH} variable, so the _GDBN__ input and output -session will proceed normally; but Emacs doesn't get enough information +session will proceed normally; but Emacs does not get enough information back from _GDBN__ to locate the source files in this situation. To avoid this problem, either start _GDBN__ mode from the directory where your program resides, or specify a full path name when prompted for the @@ -6680,7 +6732,7 @@ Execute until exit from the selected stack frame, like the _GDBN__ @code{finish} command. @item M-c -Continue execution of the program, like the _GDBN__ @code{continue} +Continue execution of your program, like the _GDBN__ @code{continue} command. @emph{Warning:} In Emacs v19, this command is @kbd{C-c C-p}. @@ -6841,9 +6893,9 @@ The fundamental principle of reporting bugs usefully is this: fact or leave it out, state it! Often people omit facts because they think they know what causes the -problem and assume that some details don't matter. Thus, you might +problem and assume that some details do not matter. Thus, you might assume that the name of the variable you use in an example does not matter. -Well, probably it doesn't, but one cannot be sure. Perhaps the bug is a +Well, probably it does not, but one cannot be sure. Perhaps the bug is a stray memory reference which happens to fetch from the location where that name is stored in memory; perhaps, if the name were different, the contents of that location would fool the debugger into doing the right thing despite @@ -6938,30 +6990,30 @@ of the original one, that is a convenience for us. Errors in the output will be easier to spot, running under the debugger will take less time, etc. -However, simplification is not vital; if you don't want to do this, +However, simplification is not vital; if you do not want to do this, report the bug anyway and send us the entire test case you used. @item A patch for the bug. -A patch for the bug does help us if it is a good one. But don't omit +A patch for the bug does help us if it is a good one. But do not omit the necessary information, such as the test case, on the assumption that a patch is all we need. We might see problems with your patch and decide to fix the problem another way, or we might not understand it at all. Sometimes with a program as complicated as _GDBN__ it is very hard to construct an example that will make the program follow a certain path -through the code. If you don't send us the example, we won't be able +through the code. If you do not send us the example, we won't be able to construct one, so we won't be able to verify that the bug is fixed. -And if we can't understand what bug you are trying to fix, or why your +And if we cannot understand what bug you are trying to fix, or why your patch should be an improvement, we won't install it. A test case will help us to understand. @item A guess about what the bug is or what it depends on. -Such guesses are usually wrong. Even we can't guess right about such +Such guesses are usually wrong. Even we cannot guess right about such things without first using the debugger to find the facts. @end itemize @@ -7135,7 +7187,7 @@ libraries @file{bfd}, @file{readline}, and @file{libiberty}, then left in the corresponding source directories. @code{configure} is a Bourne-shell (@code{/bin/sh}) script; if your -system doesn't recognize this automatically when you run a different +system does not recognize this automatically when you run a different shell, you may need to run @code{sh} on it explicitly: @samp{sh configure @var{host}}. @@ -7178,7 +7230,7 @@ does), running @code{make} in each of these directories then builds the _GDBP__ program specified there. @code{configure} creates these subdirectories for you when you -simultaneously specify several configurations; but it's a good habit +simultaneously specify several configurations; but it is a good habit even for a single configuration. You can specify the use of subdirectories using the @samp{+subdirs} option (abbreviated @samp{+sub}). For example, you can build _GDBN__ this way on a Sun 4 as @@ -7423,7 +7475,7 @@ directory tree rooted in @var{altroot}. @item +rm Remove the configuration that the other arguments specify. -@c This doesn't work (yet if ever). FIXME. +@c This does not work (yet if ever). FIXME. @c @item +parse=@var{lang} @dots{} @c Configure the _GDBN__ expression parser to parse the listed languages. @c @samp{all} configures _GDBN__ for all supported languages. To get a @@ -7487,7 +7539,7 @@ path. @file{gdb-_GDB_VN__/texinfo}: @TeX{} macros defining the GNU Documentation Format. @item -@emph{A @sc{dvi} output program.} @TeX{} doesn't actually make marks on +@emph{A @sc{dvi} output program.} @TeX{} does not actually make marks on paper; it produces output files called @sc{dvi} files. If your system has @TeX{} installed, chances are it has a program for printing out these files; one popular example is @code{dvips}, which can print @@ -7503,7 +7555,7 @@ make gdb.dvi to format the text of this manual, and print it with the usual output method for @TeX{} @sc{dvi} files at your site. -If you want to print the reference card, but don't have a PostScript +If you want to print the reference card, but do not have a PostScript printer, or you want to use Computer Modern fonts instead, you can still print it if you have @TeX{}. Format the reference card by typing @example -- 2.30.2