@c
@syncodeindex ky cp
@c FOR UPDATES LEADING TO THIS DRAFT, GDB CHANGELOG CONSULTED BETWEEN:
-@c Thu Aug 22 14:05:47 1991 Stu Grossman (grossman at cygint.cygnus.com)
+@c Fri Sep 20 16:10:52 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__.
* Signaling:: Giving the Program a Signal
* Returning:: Returning from a Function
* Calling:: Calling your Program's Functions
+* Patching:: Patching your Program
_GDBN__'s Files
contributed Intel 386 support. Jay Vosburgh contributed Symmetry
support.
-Rich Schaefer helped with support of SunOS shared libraries.
+Rich Schaefer and Peter Schauer helped with support of SunOS shared
+libraries.
Jay Fenlason and Roland McGrath ensured that GDB and GAS agree about
several machine instruction sets.
@smallexample
$ @i{_GDBP__ m4}
-Reading symbol data from m4...done.
+GDB is free software and you are welcome to distribute copies of it
+ under certain conditions; type "info copying" to see the conditions.
+There is absolutely no warranty for GDB; type "info warranty" for details.
+GDB _GDB_VN__, Copyright 1991 Free Software Foundation, Inc...
(_GDBP__)
@end smallexample
@item -quiet
@itemx -q
``Quiet''. Do not print the introductory and copyright messages. These
-messages are also suppressed in batch mode, or if an executable file name is
-specified on the _GDBN__ command line.
+messages are also suppressed in batch mode.
@item -batch
Run in batch mode. Exit with status @code{0} after processing all the command
classes.
@kindex info breakpoints
-@kindex $_
+@cindex @code{$_} and @code{info breakpoints}
@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
@c FIXME: "cannot insert breakpoints" error, v unclear.
@c Q in pending mail to Gilmore. ---pesch@cygnus.com, 26mar91
+@c some light may be shed by looking at instances of
+@c ONE_PROCESS_WRITETEXT. But error seems possible otherwise
+@c too. pesch, 20sep91
Under some operating systems, breakpoints cannot be used in a program if
any other process is running that program. In this situation,
attempting to run or continue a program with a breakpoint causes _GDBN__
@table @code
@item list @var{linenum}
-Print ten lines centered around line number @var{linenum} in the
+Print lines centered around line number @var{linenum} in the
current source file.
@item list @var{function}
-Print ten lines centered around the beginning of function
+Print lines centered around the beginning of function
@var{function}.
@item list
-Print ten more lines. If the last lines printed were printed with a
-@code{list} command, this prints ten lines following the last lines
+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 ten
+as part of displaying a stack frame (@pxref{Stack}), this prints
lines centered around that line.
@item list -
-Print ten lines just before the lines last printed.
+Print lines just before the lines last printed.
+@end table
+
+By default, _GDBN__ prints ten source lines with any of these forms of
+the @code{list} command. You can change this using @code{set listsize}:
+
+@table @code
+@item set listsize @var{count}
+@kindex set listsize
+Make the @code{list} command display @var{count} source lines (unless
+the @code{list} argument explicitly specifies some other number).
+
+@item show listsize
+@kindex show listsize
+Display the number of lines that @code{list} will currently display by
+default.
@end table
Repeating a @code{list} command with @key{RET} discards the argument,
@table @code
@item list @var{linespec}
-Print ten lines centered around the line specified by @var{linespec}.
+Print lines centered around the line specified by @var{linespec}.
@item list @var{first},@var{last}
Print lines from @var{first} to @var{last}. Both arguments are
linespecs.
@item list ,@var{last}
-Print ten lines ending with @var{last}.
+Print lines ending with @var{last}.
@item list @var{first},
-Print ten lines starting with @var{first}.
+Print lines starting with @var{first}.
@item list +
-Print ten lines just after the lines last printed.
+Print lines just after the lines last printed.
@item list -
-Print ten lines just before the lines last printed.
+Print lines just before the lines last printed.
@item list
As described in the preceding table.
Line 926 of "builtin.c" starts at pc 0x63e4 and ends at 0x6404.
@end smallexample
-@kindex $_
+@cindex @code{$_} 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
@noindent
---where the format and address are allowed to default.
-@kindex $_
-@kindex $__
+@cindex @code{$_}, @code{$__}, and value history
The addresses and contents printed by the @code{x} command are not put
in the value history because there is often too much of them and they
would get in the way. Instead, _GDBN__ makes these values available for
@table @code
@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{$_}
to that address; these commands include @code{info line} and @code{info
-breakpoint}. @code{$_}'s type is @code{void *} except when set by the
+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 $__
The variable @code{$__} is automatically set by the @code{x} command
to the value found in the last address examined. Its type is chosen
to match the format in which the data was printed.
@kindex set language
To set the language, issue the command @samp{set language @var{lang}},
-where @var{lang} is the name of a language, such as @code{c} or
-@code{m2}, or the extension of a filename written in that language, such
-as @file{.c} or @file{.mod}. For a list of the supported
-languages, type @samp{set language}.
+where @var{lang} is the name of a language: @code{c} or @code{modula-2}.
+For a list of the supported languages, type @samp{set language}.
Setting the language manually prevents _GDBN__ from updating the working
language automatically. This can lead to confusion if you try
* Signaling:: Giving the Program a Signal
* Returning:: Returning from a Function
* Calling:: Calling your Program's Functions
+* Patching:: Patching your Program
@end menu
@node Assignment, Jumping, Altering, Altering
Stepping}) resumes execution until the selected stack frame returns
naturally.@refill
-@node Calling, , Returning, Altering
+@node Calling, Patching, Returning, Altering
@section Calling your Program's Functions
@cindex calling functions
with @code{void} returned values. The result is printed and saved in
the value history, if it is not void.
+@node Patching, , Calling, Altering
+@section Patching your Program
+@cindex patching binaries
+@cindex writing into executables
+@cindex writing into corefiles
+By default, _GDBN__ opens the file containing your program's executable
+code (or the corefile) read-only. This prevents accidental alterations
+to machine code; but it also prevents you from intentionally patching
+your program's binary.
+
+If you'd like to be able to patch the binary, you can specify that
+explicitly with the @code{set write} command. For example, you might
+want to turn on internal debugging flags, or even to make emergency
+repairs.
+
+@table @code
+@item set write on
+@itemx set write off
+@kindex set write
+If you specify @samp{set write on}, _GDBN__ will open executable and
+core files for both reading and writing; if you specify @samp{set write
+off} (the default), _GDBN__ will open them read-only.
+
+If you've already loaded a file, you must load it
+again (using the @code{exec-file} or @code{core-file} command) after
+changing @code{set write}, for your new setting to take effect.
+
+@item show write
+Display whether executable files and core files will be opened for
+writing as well as reading.
+
+@end table
+
@node _GDBN__ Files, Targets, Altering, Top
@chapter _GDBN__'s Files
as arguments. _GDBN__ always converts the file name to an absolute path
name and remembers it that way.
-@kindex sharedlibrary
-@kindex share
@cindex shared libraries
-_GDBN__ supports the SunOS shared library format. Symbols from a shared
-library cannot be referenced before the shared library has been linked
-with the program. (That is to say, until after you type @code{run} and
-the function @code{main} has been entered; or when examining core
-files.) Once the shared library has been linked in, you can use the
-following commands:
+_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
+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
@table @code
-@item sharedlibrary @var{regex}
-@itemx share @var{regex}
-Load shared object library symbols for files matching a UNIX regular
-expression.
-
-@item share
-@itemx sharedlibrary
-Load symbols for all shared libraries.
-
@item info share
@itemx info sharedlibrary
@kindex info sharedlibrary
@kindex info share
-Print the names of the shared libraries which you have loaded with the
-@code{sharedlibrary} command.
-@end table
+Print the names of the shared libraries which are currently loaded.
-@code{sharedlibrary} does not repeat automatically when you press
-@key{RET} after using it once.
+@item sharedlibrary @var{regex}
+@itemx share @var{regex}
+@kindex sharedlibrary
+@kindex share
+This is an obsolescent command; you can use it to explicitly
+load shared object library symbols for files matching a UNIX regular
+expression, but as with files loaded automatically, it will only load
+shared libraries required by your program for a core file or after
+typing @code{run}. If @var{regex} is omitted all shared libraries
+required by your program are loaded.
+@end table
@node Symbol Errors, , Files, _GDBN__ Files
@section Errors Reading Symbol Files
ARCHITECTURE VENDOR OS prefix
------------+-------------+-------------
| |
- a29k | altos | aix*
- alliant | aout | aout
- arm | apollo | bout
- c1 | att | bsd*
- c2 | bout | coff
- i386 | coff | ctix*
- i860 | convergent | dynix*
- i960 | convex | esix*
- m68000 | dec | hpux*
- m68k | encore | isc*
- m88k | gould | mach*
- mips | hp | newsos*
- ns32k | ibm | nindy*
- pyramid | intel | none
- rs6000 | isi | osf*
- rtpc | little | sco*
- sparc | mips | sunos*
- tahoe | motorola | sysv*
- tron | ncr | ultrix*
- vax | next | unos*
- | none | v88r*
- | sco | vms*
- | sequent | vxworks*
- | sgi |
+ 580 | altos | aix*
+ a29k | amdahl | amigados
+ alliant | aout | aout
+ arm | apollo | bout
+ c1 | att | bsd*
+ c2 | bull | coff
+ cray2 | bcs | ctix*
+ h8300 | bout | dynix*
+ i386 | cbm | esix*
+ i860 | coff | hpux*
+ i960 | convergent | irix*
+ m68000 | convex | isc*
+ m68k | cray | kern
+ m88k | dec | mach*
+ mips | encore | newsos*
+ ns32k | gould | nindy*
+ pyramid | hp | none
+ romp | ibm | osf*
+ rs6000 | intel | sco*
+ rtpc | isi | sunos*
+ sparc | little | svr4
+ tahoe | mips | sym*
+ tron | motorola | sysv*
+ vax | ncr | ultrix*
+ xmp | next | unicos
+ ymp | none | unos*
+ | nyu | uts
+ | sco | v88r*
+ | sequent | vms*
+ | sgi | vxworks*
| sony |
| sun |
| unicom |
@end example
@end ifinfo
+@c FIXME: this table is probably screwed in @smallbook. Try setting
+@c FIXME...smallbook fonts?
@tex
-\vskip \parskip\vskip \baselineskip
-\halign{\hskip\parindent\tt #\hfil &\qquad#&\tt #\hfil &\qquad#&\tt #\hfil\cr
+%\vskip\parskip
+\vskip \baselineskip
+\halign{\hskip\parindent\tt #\hfil &\qquad#&\tt #\hfil &\qquad#&\tt
+#\hfil &\qquad\qquad\it #\hfil\cr
{\bf Architecture} &&{\bf Vendor} &&{\bf OS prefix}\cr
-\noalign{\hrule}
+\multispan5\hrulefill\cr
\cr
- a29k &&altos &&aix*\cr
- alliant &&aout &&aout\cr
- arm &&apollo &&bout\cr
- c1 &&att &&bsd*\cr
- c2 &&bout &&coff\cr
- i386 &&coff &&ctix*\cr
- i860 &&convergent &&dynix*\cr
- i960 &&convex &&esix*\cr
- m68000 &&dec &&hpux*\cr
- m68k &&encore &&isc*\cr
- m88k &&gould &&mach*\cr
- mips &&hp &&newsos*\cr
- ns32k &&ibm &&nindy*\cr
- pyramid &&intel &&none\cr
- rs6000 &&isi &&osf*\cr
- rtpc &&little &&sco*\cr
- sparc &&mips &&sunos*\cr
- tahoe &&motorola &&sysv*\cr
- tron &&ncr &&ultrix*\cr
- vax &&next &&unos*\cr
- &&none &&v88r*\cr
- &&sco &&vms*\cr
- &&sequent &&vxworks*\cr
- &&sgi \cr
- &&sony \cr
- &&sun \cr
- &&unicom \cr
- &&utek \cr
- &&wrs \cr
+ 580 && altos && aix* \cr
+ a29k && amdahl && amigados\cr
+ alliant && aout && aout \cr
+ arm && apollo && bout \cr
+ c1 && att && bsd* \cr
+ c2 && bull && coff \cr
+ cray2 && bcs && ctix* \cr
+ h8300 && bout && dynix* \cr
+ i386 && cbm && esix* \cr
+ i860 && coff && hpux* &Warning: Many combinations \cr
+ i960 && convergent && irix* &of architecture, vendor \cr
+ m68000 && convex && isc* &and OS are untested. \cr
+ m68k && cray && kern \cr
+ m88k && dec && mach* \cr
+ mips && encore && newsos* \cr
+ ns32k && gould && nindy* \cr
+ pyramid && hp && none \cr
+ romp && ibm && osf* \cr
+ rs6000 && intel && sco* \cr
+ rtpc && isi && sunos* \cr
+ sparc && little && svr4 \cr
+ tahoe && mips && sym* \cr
+ tron && motorola && sysv* \cr
+ vax && ncr && ultrix* \cr
+ xmp && next && unicos \cr
+ ymp && none && unos* \cr
+ && nyu && uts \cr
+ && sco && v88r* \cr
+ && sequent && vms* \cr
+ && sgi && vxworks*\cr
+ && sony &&\cr
+ && sun &&\cr
+ && unicom &&\cr
+ && utek &&\cr
+ && wrs &&\cr
}
@end tex
-@quotation
-@emph{Warning:} Many combinations of architecture, vendor, and OS are
-untested.
-@end quotation
The @code{configure} script accompanying _GDBN__ _GDB_VN__ does not provide
any query facility to list all supported host and target names or
projects / binutils-gdb.git / commitdiff