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This is gdb.info, produced by makeinfo version 4.8 from
../.././gdb/doc/gdb.texinfo.
INFO-DIR-SECTION Software development
START-INFO-DIR-ENTRY
* Gdb: (gdb). The GNU debugger.
END-INFO-DIR-ENTRY
This file documents the GNU debugger GDB.
This is the Ninth Edition, of `Debugging with GDB: the GNU
Source-Level Debugger' for GDB Version 6.8.
Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
1998,
1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with the
Invariant Sections being "Free Software" and "Free Software Needs Free
Documentation", with the Front-Cover Texts being "A GNU Manual," and
with the Back-Cover Texts as in (a) below.
(a) The FSF's Back-Cover Text is: "You are free to copy and modify
this GNU Manual. Buying copies from GNU Press supports the FSF in
developing GNU and promoting software freedom."

File: gdb.info, Node: GDB/MI Command Description Format, Next: GDB/MI Breakpoint Commands, Prev: GDB/MI Simple Examples, Up: GDB/MI
24.6 GDB/MI Command Description Format
======================================
The remaining sections describe blocks of commands. Each block of
commands is laid out in a fashion similar to this section.
Motivation
----------
The motivation for this collection of commands.
Introduction
------------
A brief introduction to this collection of commands as a whole.
Commands
--------
For each command in the block, the following is described:
Synopsis
........
-command ARGS...
Result
......
GDB Command
...........
The corresponding GDB CLI command(s), if any.
Example
.......
Example(s) formatted for readability. Some of the described commands
have not been implemented yet and these are labeled N.A. (not
available).

File: gdb.info, Node: GDB/MI Breakpoint Commands, Next: GDB/MI Program Context, Prev: GDB/MI Command Description Format, Up: GDB/MI
24.7 GDB/MI Breakpoint Commands
===============================
This section documents GDB/MI commands for manipulating breakpoints.
The `-break-after' Command
--------------------------
Synopsis
........
-break-after NUMBER COUNT
The breakpoint number NUMBER is not in effect until it has been hit
COUNT times. To see how this is reflected in the output of the
`-break-list' command, see the description of the `-break-list' command
below.
GDB Command
...........
The corresponding GDB command is `ignore'.
Example
.......
(gdb)
-break-insert main
^done,bkpt={number="1",addr="0x000100d0",file="hello.c",
fullname="/home/foo/hello.c",line="5",times="0"}
(gdb)
-break-after 1 3
~
^done
(gdb)
-break-list
^done,BreakpointTable={nr_rows="1",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x000100d0",func="main",file="hello.c",fullname="/home/foo/hello.c",
line="5",times="0",ignore="3"}]}
(gdb)
The `-break-condition' Command
------------------------------
Synopsis
........
-break-condition NUMBER EXPR
Breakpoint NUMBER will stop the program only if the condition in
EXPR is true. The condition becomes part of the `-break-list' output
(see the description of the `-break-list' command below).
GDB Command
...........
The corresponding GDB command is `condition'.
Example
.......
(gdb)
-break-condition 1 1
^done
(gdb)
-break-list
^done,BreakpointTable={nr_rows="1",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x000100d0",func="main",file="hello.c",fullname="/home/foo/hello.c",
line="5",cond="1",times="0",ignore="3"}]}
(gdb)
The `-break-delete' Command
---------------------------
Synopsis
........
-break-delete ( BREAKPOINT )+
Delete the breakpoint(s) whose number(s) are specified in the
argument list. This is obviously reflected in the breakpoint list.
GDB Command
...........
The corresponding GDB command is `delete'.
Example
.......
(gdb)
-break-delete 1
^done
(gdb)
-break-list
^done,BreakpointTable={nr_rows="0",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[]}
(gdb)
The `-break-disable' Command
----------------------------
Synopsis
........
-break-disable ( BREAKPOINT )+
Disable the named BREAKPOINT(s). The field `enabled' in the break
list is now set to `n' for the named BREAKPOINT(s).
GDB Command
...........
The corresponding GDB command is `disable'.
Example
.......
(gdb)
-break-disable 2
^done
(gdb)
-break-list
^done,BreakpointTable={nr_rows="1",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="2",type="breakpoint",disp="keep",enabled="n",
addr="0x000100d0",func="main",file="hello.c",fullname="/home/foo/hello.c",
line="5",times="0"}]}
(gdb)
The `-break-enable' Command
---------------------------
Synopsis
........
-break-enable ( BREAKPOINT )+
Enable (previously disabled) BREAKPOINT(s).
GDB Command
...........
The corresponding GDB command is `enable'.
Example
.......
(gdb)
-break-enable 2
^done
(gdb)
-break-list
^done,BreakpointTable={nr_rows="1",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="2",type="breakpoint",disp="keep",enabled="y",
addr="0x000100d0",func="main",file="hello.c",fullname="/home/foo/hello.c",
line="5",times="0"}]}
(gdb)
The `-break-info' Command
-------------------------
Synopsis
........
-break-info BREAKPOINT
Get information about a single breakpoint.
GDB Command
...........
The corresponding GDB command is `info break BREAKPOINT'.
Example
.......
N.A.
The `-break-insert' Command
---------------------------
Synopsis
........
-break-insert [ -t ] [ -h ] [ -f ]
[ -c CONDITION ] [ -i IGNORE-COUNT ]
[ -p THREAD ] [ LOCATION ]
If specified, LOCATION, can be one of:
* function
* filename:linenum
* filename:function
* *address
The possible optional parameters of this command are:
`-t'
Insert a temporary breakpoint.
`-h'
Insert a hardware breakpoint.
`-c CONDITION'
Make the breakpoint conditional on CONDITION.
`-i IGNORE-COUNT'
Initialize the IGNORE-COUNT.
`-f'
If LOCATION cannot be parsed (for example if it refers to unknown
files or functions), create a pending breakpoint. Without this
flag, GDB will report an error, and won't create a breakpoint, if
LOCATION cannot be parsed.
Result
......
The result is in the form:
^done,bkpt={number="NUMBER",type="TYPE",disp="del"|"keep",
enabled="y"|"n",addr="HEX",func="FUNCNAME",file="FILENAME",
fullname="FULL_FILENAME",line="LINENO",[thread="THREADNO,]
times="TIMES"}
where NUMBER is the GDB number for this breakpoint, FUNCNAME is the
name of the function where the breakpoint was inserted, FILENAME is the
name of the source file which contains this function, LINENO is the
source line number within that file and TIMES the number of times that
the breakpoint has been hit (always 0 for -break-insert but may be
greater for -break-info or -break-list which use the same output).
Note: this format is open to change.
GDB Command
...........
The corresponding GDB commands are `break', `tbreak', `hbreak',
`thbreak', and `rbreak'.
Example
.......
(gdb)
-break-insert main
^done,bkpt={number="1",addr="0x0001072c",file="recursive2.c",
fullname="/home/foo/recursive2.c,line="4",times="0"}
(gdb)
-break-insert -t foo
^done,bkpt={number="2",addr="0x00010774",file="recursive2.c",
fullname="/home/foo/recursive2.c,line="11",times="0"}
(gdb)
-break-list
^done,BreakpointTable={nr_rows="2",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x0001072c", func="main",file="recursive2.c",
fullname="/home/foo/recursive2.c,"line="4",times="0"},
bkpt={number="2",type="breakpoint",disp="del",enabled="y",
addr="0x00010774",func="foo",file="recursive2.c",
fullname="/home/foo/recursive2.c",line="11",times="0"}]}
(gdb)
-break-insert -r foo.*
~int foo(int, int);
^done,bkpt={number="3",addr="0x00010774",file="recursive2.c,
"fullname="/home/foo/recursive2.c",line="11",times="0"}
(gdb)
The `-break-list' Command
-------------------------
Synopsis
........
-break-list
Displays the list of inserted breakpoints, showing the following
fields:
`Number'
number of the breakpoint
`Type'
type of the breakpoint: `breakpoint' or `watchpoint'
`Disposition'
should the breakpoint be deleted or disabled when it is hit: `keep'
or `nokeep'
`Enabled'
is the breakpoint enabled or no: `y' or `n'
`Address'
memory location at which the breakpoint is set
`What'
logical location of the breakpoint, expressed by function name,
file name, line number
`Times'
number of times the breakpoint has been hit
If there are no breakpoints or watchpoints, the `BreakpointTable'
`body' field is an empty list.
GDB Command
...........
The corresponding GDB command is `info break'.
Example
.......
(gdb)
-break-list
^done,BreakpointTable={nr_rows="2",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x000100d0",func="main",file="hello.c",line="5",times="0"},
bkpt={number="2",type="breakpoint",disp="keep",enabled="y",
addr="0x00010114",func="foo",file="hello.c",fullname="/home/foo/hello.c",
line="13",times="0"}]}
(gdb)
Here's an example of the result when there are no breakpoints:
(gdb)
-break-list
^done,BreakpointTable={nr_rows="0",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[]}
(gdb)
The `-break-watch' Command
--------------------------
Synopsis
........
-break-watch [ -a | -r ]
Create a watchpoint. With the `-a' option it will create an
"access" watchpoint, i.e., a watchpoint that triggers either on a read
from or on a write to the memory location. With the `-r' option, the
watchpoint created is a "read" watchpoint, i.e., it will trigger only
when the memory location is accessed for reading. Without either of
the options, the watchpoint created is a regular watchpoint, i.e., it
will trigger when the memory location is accessed for writing. *Note
Setting Watchpoints: Set Watchpoints.
Note that `-break-list' will report a single list of watchpoints and
breakpoints inserted.
GDB Command
...........
The corresponding GDB commands are `watch', `awatch', and `rwatch'.
Example
.......
Setting a watchpoint on a variable in the `main' function:
(gdb)
-break-watch x
^done,wpt={number="2",exp="x"}
(gdb)
-exec-continue
^running
(gdb)
*stopped,reason="watchpoint-trigger",wpt={number="2",exp="x"},
value={old="-268439212",new="55"},
frame={func="main",args=[],file="recursive2.c",
fullname="/home/foo/bar/recursive2.c",line="5"}
(gdb)
Setting a watchpoint on a variable local to a function. GDB will
stop the program execution twice: first for the variable changing
value, then for the watchpoint going out of scope.
(gdb)
-break-watch C
^done,wpt={number="5",exp="C"}
(gdb)
-exec-continue
^running
(gdb)
*stopped,reason="watchpoint-trigger",
wpt={number="5",exp="C"},value={old="-276895068",new="3"},
frame={func="callee4",args=[],
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="13"}
(gdb)
-exec-continue
^running
(gdb)
*stopped,reason="watchpoint-scope",wpnum="5",
frame={func="callee3",args=[{name="strarg",
value="0x11940 \"A string argument.\""}],
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="18"}
(gdb)
Listing breakpoints and watchpoints, at different points in the
program execution. Note that once the watchpoint goes out of scope, it
is deleted.
(gdb)
-break-watch C
^done,wpt={number="2",exp="C"}
(gdb)
-break-list
^done,BreakpointTable={nr_rows="2",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x00010734",func="callee4",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/devo/gdb/testsuite/gdb.mi/basics.c"line="8",times="1"},
bkpt={number="2",type="watchpoint",disp="keep",
enabled="y",addr="",what="C",times="0"}]}
(gdb)
-exec-continue
^running
(gdb)
*stopped,reason="watchpoint-trigger",wpt={number="2",exp="C"},
value={old="-276895068",new="3"},
frame={func="callee4",args=[],
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="13"}
(gdb)
-break-list
^done,BreakpointTable={nr_rows="2",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x00010734",func="callee4",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/devo/gdb/testsuite/gdb.mi/basics.c",line="8",times="1"},
bkpt={number="2",type="watchpoint",disp="keep",
enabled="y",addr="",what="C",times="-5"}]}
(gdb)
-exec-continue
^running
^done,reason="watchpoint-scope",wpnum="2",
frame={func="callee3",args=[{name="strarg",
value="0x11940 \"A string argument.\""}],
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="18"}
(gdb)
-break-list
^done,BreakpointTable={nr_rows="1",nr_cols="6",
hdr=[{width="3",alignment="-1",col_name="number",colhdr="Num"},
{width="14",alignment="-1",col_name="type",colhdr="Type"},
{width="4",alignment="-1",col_name="disp",colhdr="Disp"},
{width="3",alignment="-1",col_name="enabled",colhdr="Enb"},
{width="10",alignment="-1",col_name="addr",colhdr="Address"},
{width="40",alignment="2",col_name="what",colhdr="What"}],
body=[bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x00010734",func="callee4",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/devo/gdb/testsuite/gdb.mi/basics.c",line="8",
times="1"}]}
(gdb)

File: gdb.info, Node: GDB/MI Program Context, Next: GDB/MI Thread Commands, Prev: GDB/MI Breakpoint Commands, Up: GDB/MI
24.8 GDB/MI Program Context
============================
The `-exec-arguments' Command
-----------------------------
Synopsis
........
-exec-arguments ARGS
Set the inferior program arguments, to be used in the next
`-exec-run'.
GDB Command
...........
The corresponding GDB command is `set args'.
Example
.......
Don't have one around.
The `-exec-show-arguments' Command
----------------------------------
Synopsis
........
-exec-show-arguments
Print the arguments of the program.
GDB Command
...........
The corresponding GDB command is `show args'.
Example
.......
N.A.
The `-environment-cd' Command
-----------------------------
Synopsis
........
-environment-cd PATHDIR
Set GDB's working directory.
GDB Command
...........
The corresponding GDB command is `cd'.
Example
.......
(gdb)
-environment-cd /kwikemart/marge/ezannoni/flathead-dev/devo/gdb
^done
(gdb)
The `-environment-directory' Command
------------------------------------
Synopsis
........
-environment-directory [ -r ] [ PATHDIR ]+
Add directories PATHDIR to beginning of search path for source files.
If the `-r' option is used, the search path is reset to the default
search path. If directories PATHDIR are supplied in addition to the
`-r' option, the search path is first reset and then addition occurs as
normal. Multiple directories may be specified, separated by blanks.
Specifying multiple directories in a single command results in the
directories added to the beginning of the search path in the same order
they were presented in the command. If blanks are needed as part of a
directory name, double-quotes should be used around the name. In the
command output, the path will show up separated by the system
directory-separator character. The directory-separator character must
not be used in any directory name. If no directories are specified,
the current search path is displayed.
GDB Command
...........
The corresponding GDB command is `dir'.
Example
.......
(gdb)
-environment-directory /kwikemart/marge/ezannoni/flathead-dev/devo/gdb
^done,source-path="/kwikemart/marge/ezannoni/flathead-dev/devo/gdb:$cdir:$cwd"
(gdb)
-environment-directory ""
^done,source-path="/kwikemart/marge/ezannoni/flathead-dev/devo/gdb:$cdir:$cwd"
(gdb)
-environment-directory -r /home/jjohnstn/src/gdb /usr/src
^done,source-path="/home/jjohnstn/src/gdb:/usr/src:$cdir:$cwd"
(gdb)
-environment-directory -r
^done,source-path="$cdir:$cwd"
(gdb)
The `-environment-path' Command
-------------------------------
Synopsis
........
-environment-path [ -r ] [ PATHDIR ]+
Add directories PATHDIR to beginning of search path for object files.
If the `-r' option is used, the search path is reset to the original
search path that existed at gdb start-up. If directories PATHDIR are
supplied in addition to the `-r' option, the search path is first reset
and then addition occurs as normal. Multiple directories may be
specified, separated by blanks. Specifying multiple directories in a
single command results in the directories added to the beginning of the
search path in the same order they were presented in the command. If
blanks are needed as part of a directory name, double-quotes should be
used around the name. In the command output, the path will show up
separated by the system directory-separator character. The
directory-separator character must not be used in any directory name.
If no directories are specified, the current path is displayed.
GDB Command
...........
The corresponding GDB command is `path'.
Example
.......
(gdb)
-environment-path
^done,path="/usr/bin"
(gdb)
-environment-path /kwikemart/marge/ezannoni/flathead-dev/ppc-eabi/gdb /bin
^done,path="/kwikemart/marge/ezannoni/flathead-dev/ppc-eabi/gdb:/bin:/usr/bin"
(gdb)
-environment-path -r /usr/local/bin
^done,path="/usr/local/bin:/usr/bin"
(gdb)
The `-environment-pwd' Command
------------------------------
Synopsis
........
-environment-pwd
Show the current working directory.
GDB Command
...........
The corresponding GDB command is `pwd'.
Example
.......
(gdb)
-environment-pwd
^done,cwd="/kwikemart/marge/ezannoni/flathead-dev/devo/gdb"
(gdb)

File: gdb.info, Node: GDB/MI Thread Commands, Next: GDB/MI Program Execution, Prev: GDB/MI Program Context, Up: GDB/MI
24.9 GDB/MI Thread Commands
===========================
The `-thread-info' Command
--------------------------
Synopsis
........
-thread-info
GDB Command
...........
No equivalent.
Example
.......
N.A.
The `-thread-list-all-threads' Command
--------------------------------------
Synopsis
........
-thread-list-all-threads
GDB Command
...........
The equivalent GDB command is `info threads'.
Example
.......
N.A.
The `-thread-list-ids' Command
------------------------------
Synopsis
........
-thread-list-ids
Produces a list of the currently known GDB thread ids. At the end
of the list it also prints the total number of such threads.
GDB Command
...........
Part of `info threads' supplies the same information.
Example
.......
No threads present, besides the main process:
(gdb)
-thread-list-ids
^done,thread-ids={},number-of-threads="0"
(gdb)
Several threads:
(gdb)
-thread-list-ids
^done,thread-ids={thread-id="3",thread-id="2",thread-id="1"},
number-of-threads="3"
(gdb)
The `-thread-select' Command
----------------------------
Synopsis
........
-thread-select THREADNUM
Make THREADNUM the current thread. It prints the number of the new
current thread, and the topmost frame for that thread.
GDB Command
...........
The corresponding GDB command is `thread'.
Example
.......
(gdb)
-exec-next
^running
(gdb)
*stopped,reason="end-stepping-range",thread-id="2",line="187",
file="../../../devo/gdb/testsuite/gdb.threads/linux-dp.c"
(gdb)
-thread-list-ids
^done,
thread-ids={thread-id="3",thread-id="2",thread-id="1"},
number-of-threads="3"
(gdb)
-thread-select 3
^done,new-thread-id="3",
frame={level="0",func="vprintf",
args=[{name="format",value="0x8048e9c \"%*s%c %d %c\\n\""},
{name="arg",value="0x2"}],file="vprintf.c",line="31"}
(gdb)

File: gdb.info, Node: GDB/MI Program Execution, Next: GDB/MI Stack Manipulation, Prev: GDB/MI Thread Commands, Up: GDB/MI
24.10 GDB/MI Program Execution
==============================
These are the asynchronous commands which generate the out-of-band
record `*stopped'. Currently GDB only really executes asynchronously
with remote targets and this interaction is mimicked in other cases.
The `-exec-continue' Command
----------------------------
Synopsis
........
-exec-continue
Resumes the execution of the inferior program until a breakpoint is
encountered, or until the inferior exits.
GDB Command
...........
The corresponding GDB corresponding is `continue'.
Example
.......
-exec-continue
^running
(gdb)
@Hello world
*stopped,reason="breakpoint-hit",bkptno="2",frame={func="foo",args=[],
file="hello.c",fullname="/home/foo/bar/hello.c",line="13"}
(gdb)
The `-exec-finish' Command
--------------------------
Synopsis
........
-exec-finish
Resumes the execution of the inferior program until the current
function is exited. Displays the results returned by the function.
GDB Command
...........
The corresponding GDB command is `finish'.
Example
.......
Function returning `void'.
-exec-finish
^running
(gdb)
@hello from foo
*stopped,reason="function-finished",frame={func="main",args=[],
file="hello.c",fullname="/home/foo/bar/hello.c",line="7"}
(gdb)
Function returning other than `void'. The name of the internal GDB
variable storing the result is printed, together with the value itself.
-exec-finish
^running
(gdb)
*stopped,reason="function-finished",frame={addr="0x000107b0",func="foo",
args=[{name="a",value="1"],{name="b",value="9"}},
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
gdb-result-var="$1",return-value="0"
(gdb)
The `-exec-interrupt' Command
-----------------------------
Synopsis
........
-exec-interrupt
Interrupts the background execution of the target. Note how the
token associated with the stop message is the one for the execution
command that has been interrupted. The token for the interrupt itself
only appears in the `^done' output. If the user is trying to interrupt
a non-running program, an error message will be printed.
GDB Command
...........
The corresponding GDB command is `interrupt'.
Example
.......
(gdb)
111-exec-continue
111^running
(gdb)
222-exec-interrupt
222^done
(gdb)
111*stopped,signal-name="SIGINT",signal-meaning="Interrupt",
frame={addr="0x00010140",func="foo",args=[],file="try.c",
fullname="/home/foo/bar/try.c",line="13"}
(gdb)
(gdb)
-exec-interrupt
^error,msg="mi_cmd_exec_interrupt: Inferior not executing."
(gdb)
The `-exec-next' Command
------------------------
Synopsis
........
-exec-next
Resumes execution of the inferior program, stopping when the
beginning of the next source line is reached.
GDB Command
...........
The corresponding GDB command is `next'.
Example
.......
-exec-next
^running
(gdb)
*stopped,reason="end-stepping-range",line="8",file="hello.c"
(gdb)
The `-exec-next-instruction' Command
------------------------------------
Synopsis
........
-exec-next-instruction
Executes one machine instruction. If the instruction is a function
call, continues until the function returns. If the program stops at an
instruction in the middle of a source line, the address will be printed
as well.
GDB Command
...........
The corresponding GDB command is `nexti'.
Example
.......
(gdb)
-exec-next-instruction
^running
(gdb)
*stopped,reason="end-stepping-range",
addr="0x000100d4",line="5",file="hello.c"
(gdb)
The `-exec-return' Command
--------------------------
Synopsis
........
-exec-return
Makes current function return immediately. Doesn't execute the
inferior. Displays the new current frame.
GDB Command
...........
The corresponding GDB command is `return'.
Example
.......
(gdb)
200-break-insert callee4
200^done,bkpt={number="1",addr="0x00010734",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",line="8"}
(gdb)
000-exec-run
000^running
(gdb)
000*stopped,reason="breakpoint-hit",bkptno="1",
frame={func="callee4",args=[],
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="8"}
(gdb)
205-break-delete
205^done
(gdb)
111-exec-return
111^done,frame={level="0",func="callee3",
args=[{name="strarg",
value="0x11940 \"A string argument.\""}],
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="18"}
(gdb)
The `-exec-run' Command
-----------------------
Synopsis
........
-exec-run
Starts execution of the inferior from the beginning. The inferior
executes until either a breakpoint is encountered or the program exits.
In the latter case the output will include an exit code, if the
program has exited exceptionally.
GDB Command
...........
The corresponding GDB command is `run'.
Examples
........
(gdb)
-break-insert main
^done,bkpt={number="1",addr="0x0001072c",file="recursive2.c",line="4"}
(gdb)
-exec-run
^running
(gdb)
*stopped,reason="breakpoint-hit",bkptno="1",
frame={func="main",args=[],file="recursive2.c",
fullname="/home/foo/bar/recursive2.c",line="4"}
(gdb)
Program exited normally:
(gdb)
-exec-run
^running
(gdb)
x = 55
*stopped,reason="exited-normally"
(gdb)
Program exited exceptionally:
(gdb)
-exec-run
^running
(gdb)
x = 55
*stopped,reason="exited",exit-code="01"
(gdb)
Another way the program can terminate is if it receives a signal
such as `SIGINT'. In this case, GDB/MI displays this:
(gdb)
*stopped,reason="exited-signalled",signal-name="SIGINT",
signal-meaning="Interrupt"
The `-exec-step' Command
------------------------
Synopsis
........
-exec-step
Resumes execution of the inferior program, stopping when the
beginning of the next source line is reached, if the next source line
is not a function call. If it is, stop at the first instruction of the
called function.
GDB Command
...........
The corresponding GDB command is `step'.
Example
.......
Stepping into a function:
-exec-step
^running
(gdb)
*stopped,reason="end-stepping-range",
frame={func="foo",args=[{name="a",value="10"},
{name="b",value="0"}],file="recursive2.c",
fullname="/home/foo/bar/recursive2.c",line="11"}
(gdb)
Regular stepping:
-exec-step
^running
(gdb)
*stopped,reason="end-stepping-range",line="14",file="recursive2.c"
(gdb)
The `-exec-step-instruction' Command
------------------------------------
Synopsis
........
-exec-step-instruction
Resumes the inferior which executes one machine instruction. The
output, once GDB has stopped, will vary depending on whether we have
stopped in the middle of a source line or not. In the former case, the
address at which the program stopped will be printed as well.
GDB Command
...........
The corresponding GDB command is `stepi'.
Example
.......
(gdb)
-exec-step-instruction
^running
(gdb)
*stopped,reason="end-stepping-range",
frame={func="foo",args=[],file="try.c",
fullname="/home/foo/bar/try.c",line="10"}
(gdb)
-exec-step-instruction
^running
(gdb)
*stopped,reason="end-stepping-range",
frame={addr="0x000100f4",func="foo",args=[],file="try.c",
fullname="/home/foo/bar/try.c",line="10"}
(gdb)
The `-exec-until' Command
-------------------------
Synopsis
........
-exec-until [ LOCATION ]
Executes the inferior until the LOCATION specified in the argument
is reached. If there is no argument, the inferior executes until a
source line greater than the current one is reached. The reason for
stopping in this case will be `location-reached'.
GDB Command
...........
The corresponding GDB command is `until'.
Example
.......
(gdb)
-exec-until recursive2.c:6
^running
(gdb)
x = 55
*stopped,reason="location-reached",frame={func="main",args=[],
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="6"}
(gdb)

File: gdb.info, Node: GDB/MI Stack Manipulation, Next: GDB/MI Variable Objects, Prev: GDB/MI Program Execution, Up: GDB/MI
24.11 GDB/MI Stack Manipulation Commands
========================================
The `-stack-info-frame' Command
-------------------------------
Synopsis
........
-stack-info-frame
Get info on the selected frame.
GDB Command
...........
The corresponding GDB command is `info frame' or `frame' (without
arguments).
Example
.......
(gdb)
-stack-info-frame
^done,frame={level="1",addr="0x0001076c",func="callee3",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="17"}
(gdb)
The `-stack-info-depth' Command
-------------------------------
Synopsis
........
-stack-info-depth [ MAX-DEPTH ]
Return the depth of the stack. If the integer argument MAX-DEPTH is
specified, do not count beyond MAX-DEPTH frames.
GDB Command
...........
There's no equivalent GDB command.
Example
.......
For a stack with frame levels 0 through 11:
(gdb)
-stack-info-depth
^done,depth="12"
(gdb)
-stack-info-depth 4
^done,depth="4"
(gdb)
-stack-info-depth 12
^done,depth="12"
(gdb)
-stack-info-depth 11
^done,depth="11"
(gdb)
-stack-info-depth 13
^done,depth="12"
(gdb)
The `-stack-list-arguments' Command
-----------------------------------
Synopsis
........
-stack-list-arguments SHOW-VALUES
[ LOW-FRAME HIGH-FRAME ]
Display a list of the arguments for the frames between LOW-FRAME and
HIGH-FRAME (inclusive). If LOW-FRAME and HIGH-FRAME are not provided,
list the arguments for the whole call stack. If the two arguments are
equal, show the single frame at the corresponding level. It is an
error if LOW-FRAME is larger than the actual number of frames. On the
other hand, HIGH-FRAME may be larger than the actual number of frames,
in which case only existing frames will be returned.
The SHOW-VALUES argument must have a value of 0 or 1. A value of 0
means that only the names of the arguments are listed, a value of 1
means that both names and values of the arguments are printed.
GDB Command
...........
GDB does not have an equivalent command. `gdbtk' has a `gdb_get_args'
command which partially overlaps with the functionality of
`-stack-list-arguments'.
Example
.......
(gdb)
-stack-list-frames
^done,
stack=[
frame={level="0",addr="0x00010734",func="callee4",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="8"},
frame={level="1",addr="0x0001076c",func="callee3",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="17"},
frame={level="2",addr="0x0001078c",func="callee2",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="22"},
frame={level="3",addr="0x000107b4",func="callee1",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="27"},
frame={level="4",addr="0x000107e0",func="main",
file="../../../devo/gdb/testsuite/gdb.mi/basics.c",
fullname="/home/foo/bar/devo/gdb/testsuite/gdb.mi/basics.c",line="32"}]
(gdb)
-stack-list-arguments 0
^done,
stack-args=[
frame={level="0",args=[]},
frame={level="1",args=[name="strarg"]},
frame={level="2",args=[name="intarg",name="strarg"]},
frame={level="3",args=[name="intarg",name="strarg",name="fltarg"]},
frame={level="4",args=[]}]
(gdb)
-stack-list-arguments 1
^done,
stack-args=[
frame={level="0",args=[]},
frame={level="1",
args=[{name="strarg",value="0x11940 \"A string argument.\""}]},
frame={level="2",args=[
{name="intarg",value="2"},
{name="strarg",value="0x11940 \"A string argument.\""}]},
{frame={level="3",args=[
{name="intarg",value="2"},
{name="strarg",value="0x11940 \"A string argument.\""},
{name="fltarg",value="3.5"}]},
frame={level="4",args=[]}]
(gdb)
-stack-list-arguments 0 2 2
^done,stack-args=[frame={level="2",args=[name="intarg",name="strarg"]}]
(gdb)
-stack-list-arguments 1 2 2
^done,stack-args=[frame={level="2",
args=[{name="intarg",value="2"},
{name="strarg",value="0x11940 \"A string argument.\""}]}]
(gdb)
The `-stack-list-frames' Command
--------------------------------
Synopsis
........
-stack-list-frames [ LOW-FRAME HIGH-FRAME ]
List the frames currently on the stack. For each frame it displays
the following info:
`LEVEL'
The frame number, 0 being the topmost frame, i.e., the innermost
function.
`ADDR'
The `$pc' value for that frame.
`FUNC'
Function name.
`FILE'
File name of the source file where the function lives.
`LINE'
Line number corresponding to the `$pc'.
If invoked without arguments, this command prints a backtrace for the
whole stack. If given two integer arguments, it shows the frames whose
levels are between the two arguments (inclusive). If the two arguments
are equal, it shows the single frame at the corresponding level. It is
an error if LOW-FRAME is larger than the actual number of frames. On
the other hand, HIGH-FRAME may be larger than the actual number of
frames, in which case only existing frames will be returned.
GDB Command
...........
The corresponding GDB commands are `backtrace' and `where'.
Example
.......
Full stack backtrace:
(gdb)
-stack-list-frames
^done,stack=
[frame={level="0",addr="0x0001076c",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="11"},
frame={level="1",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="2",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="3",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="4",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="5",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="6",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="7",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="8",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="9",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="10",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="11",addr="0x00010738",func="main",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="4"}]
(gdb)
Show frames between LOW_FRAME and HIGH_FRAME:
(gdb)
-stack-list-frames 3 5
^done,stack=
[frame={level="3",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="4",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"},
frame={level="5",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"}]
(gdb)
Show a single frame:
(gdb)
-stack-list-frames 3 3
^done,stack=
[frame={level="3",addr="0x000107a4",func="foo",
file="recursive2.c",fullname="/home/foo/bar/recursive2.c",line="14"}]
(gdb)
The `-stack-list-locals' Command
--------------------------------
Synopsis
........
-stack-list-locals PRINT-VALUES
Display the local variable names for the selected frame. If
PRINT-VALUES is 0 or `--no-values', print only the names of the
variables; if it is 1 or `--all-values', print also their values; and
if it is 2 or `--simple-values', print the name, type and value for
simple data types and the name and type for arrays, structures and
unions. In this last case, a frontend can immediately display the
value of simple data types and create variable objects for other data
types when the user wishes to explore their values in more detail.
GDB Command
...........
`info locals' in GDB, `gdb_get_locals' in `gdbtk'.
Example
.......
(gdb)
-stack-list-locals 0
^done,locals=[name="A",name="B",name="C"]
(gdb)
-stack-list-locals --all-values
^done,locals=[{name="A",value="1"},{name="B",value="2"},
{name="C",value="{1, 2, 3}"}]
-stack-list-locals --simple-values
^done,locals=[{name="A",type="int",value="1"},
{name="B",type="int",value="2"},{name="C",type="int [3]"}]
(gdb)
The `-stack-select-frame' Command
---------------------------------
Synopsis
........
-stack-select-frame FRAMENUM
Change the selected frame. Select a different frame FRAMENUM on the
stack.
GDB Command
...........
The corresponding GDB commands are `frame', `up', `down',
`select-frame', `up-silent', and `down-silent'.
Example
.......
(gdb)
-stack-select-frame 2
^done
(gdb)

File: gdb.info, Node: GDB/MI Variable Objects, Next: GDB/MI Data Manipulation, Prev: GDB/MI Stack Manipulation, Up: GDB/MI
24.12 GDB/MI Variable Objects
=============================
Introduction to Variable Objects
--------------------------------
Variable objects are "object-oriented" MI interface for examining and
changing values of expressions. Unlike some other MI interfaces that
work with expressions, variable objects are specifically designed for
simple and efficient presentation in the frontend. A variable object
is identified by string name. When a variable object is created, the
frontend specifies the expression for that variable object. The
expression can be a simple variable, or it can be an arbitrary complex
expression, and can even involve CPU registers. After creating a
variable object, the frontend can invoke other variable object
operations--for example to obtain or change the value of a variable
object, or to change display format.
Variable objects have hierarchical tree structure. Any variable
object that corresponds to a composite type, such as structure in C, has
a number of child variable objects, for example corresponding to each
element of a structure. A child variable object can itself have
children, recursively. Recursion ends when we reach leaf variable
objects, which always have built-in types. Child variable objects are
created only by explicit request, so if a frontend is not interested in
the children of a particular variable object, no child will be created.
For a leaf variable object it is possible to obtain its value as a
string, or set the value from a string. String value can be also
obtained for a non-leaf variable object, but it's generally a string
that only indicates the type of the object, and does not list its
contents. Assignment to a non-leaf variable object is not allowed.
A frontend does not need to read the values of all variable objects
each time the program stops. Instead, MI provides an update command
that lists all variable objects whose values has changed since the last
update operation. This considerably reduces the amount of data that
must be transferred to the frontend. As noted above, children variable
objects are created on demand, and only leaf variable objects have a
real value. As result, gdb will read target memory only for leaf
variables that frontend has created.
The automatic update is not always desirable. For example, a
frontend might want to keep a value of some expression for future
reference, and never update it. For another example, fetching memory
is relatively slow for embedded targets, so a frontend might want to
disable automatic update for the variables that are either not visible
on the screen, or "closed". This is possible using so called "frozen
variable objects". Such variable objects are never implicitly updated.
The following is the complete set of GDB/MI operations defined to
access this functionality:
*Operation* *Description*
`-var-create' create a variable object
`-var-delete' delete the variable object and/or its
children
`-var-set-format' set the display format of this variable
`-var-show-format' show the display format of this variable
`-var-info-num-children' tells how many children this object has
`-var-list-children' return a list of the object's children
`-var-info-type' show the type of this variable object
`-var-info-expression' print parent-relative expression that this
variable object represents
`-var-info-path-expression' print full expression that this variable
object represents
`-var-show-attributes' is this variable editable? does it exist
here?
`-var-evaluate-expression' get the value of this variable
`-var-assign' set the value of this variable
`-var-update' update the variable and its children
`-var-set-frozen' set frozeness attribute
In the next subsection we describe each operation in detail and
suggest how it can be used.
Description And Use of Operations on Variable Objects
-----------------------------------------------------
The `-var-create' Command
-------------------------
Synopsis
........
-var-create {NAME | "-"}
{FRAME-ADDR | "*"} EXPRESSION
This operation creates a variable object, which allows the
monitoring of a variable, the result of an expression, a memory cell or
a CPU register.
The NAME parameter is the string by which the object can be
referenced. It must be unique. If `-' is specified, the varobj system
will generate a string "varNNNNNN" automatically. It will be unique
provided that one does not specify NAME on that format. The command
fails if a duplicate name is found.
The frame under which the expression should be evaluated can be
specified by FRAME-ADDR. A `*' indicates that the current frame should
be used.
EXPRESSION is any expression valid on the current language set (must
not begin with a `*'), or one of the following:
* `*ADDR', where ADDR is the address of a memory cell
* `*ADDR-ADDR' -- a memory address range (TBD)
* `$REGNAME' -- a CPU register name
Result
......
This operation returns the name, number of children and the type of the
object created. Type is returned as a string as the ones generated by
the GDB CLI:
name="NAME",numchild="N",type="TYPE"
The `-var-delete' Command
-------------------------
Synopsis
........
-var-delete [ -c ] NAME
Deletes a previously created variable object and all of its children.
With the `-c' option, just deletes the children.
Returns an error if the object NAME is not found.
The `-var-set-format' Command
-----------------------------
Synopsis
........
-var-set-format NAME FORMAT-SPEC
Sets the output format for the value of the object NAME to be
FORMAT-SPEC.
The syntax for the FORMAT-SPEC is as follows:
FORMAT-SPEC ==>
{binary | decimal | hexadecimal | octal | natural}
The natural format is the default format choosen automatically based
on the variable type (like decimal for an `int', hex for pointers,
etc.).
For a variable with children, the format is set only on the variable
itself, and the children are not affected.
The `-var-show-format' Command
------------------------------
Synopsis
........
-var-show-format NAME
Returns the format used to display the value of the object NAME.
FORMAT ==>
FORMAT-SPEC
The `-var-info-num-children' Command
------------------------------------
Synopsis
........
-var-info-num-children NAME
Returns the number of children of a variable object NAME:
numchild=N
The `-var-list-children' Command
--------------------------------
Synopsis
........
-var-list-children [PRINT-VALUES] NAME
Return a list of the children of the specified variable object and
create variable objects for them, if they do not already exist. With a
single argument or if PRINT-VALUES has a value for of 0 or
`--no-values', print only the names of the variables; if PRINT-VALUES
is 1 or `--all-values', also print their values; and if it is 2 or
`--simple-values' print the name and value for simple data types and
just the name for arrays, structures and unions.
Example
.......
(gdb)
-var-list-children n
^done,numchild=N,children=[{name=NAME,
numchild=N,type=TYPE},(repeats N times)]
(gdb)
-var-list-children --all-values n
^done,numchild=N,children=[{name=NAME,
numchild=N,value=VALUE,type=TYPE},(repeats N times)]
The `-var-info-type' Command
----------------------------
Synopsis
........
-var-info-type NAME
Returns the type of the specified variable NAME. The type is
returned as a string in the same format as it is output by the GDB CLI:
type=TYPENAME
The `-var-info-expression' Command
----------------------------------
Synopsis
........
-var-info-expression NAME
Returns a string that is suitable for presenting this variable
object in user interface. The string is generally not valid expression
in the current language, and cannot be evaluated.
For example, if `a' is an array, and variable object `A' was created
for `a', then we'll get this output:
(gdb) -var-info-expression A.1
^done,lang="C",exp="1"
Here, the values of `lang' can be `{"C" | "C++" | "Java"}'.
Note that the output of the `-var-list-children' command also
includes those expressions, so the `-var-info-expression' command is of
limited use.
The `-var-info-path-expression' Command
---------------------------------------
Synopsis
........
-var-info-path-expression NAME
Returns an expression that can be evaluated in the current context
and will yield the same value that a variable object has. Compare this
with the `-var-info-expression' command, which result can be used only
for UI presentation. Typical use of the `-var-info-path-expression'
command is creating a watchpoint from a variable object.
For example, suppose `C' is a C++ class, derived from class `Base',
and that the `Base' class has a member called `m_size'. Assume a
variable `c' is has the type of `C' and a variable object `C' was
created for variable `c'. Then, we'll get this output:
(gdb) -var-info-path-expression C.Base.public.m_size
^done,path_expr=((Base)c).m_size)
The `-var-show-attributes' Command
----------------------------------
Synopsis
........
-var-show-attributes NAME
List attributes of the specified variable object NAME:
status=ATTR [ ( ,ATTR )* ]
where ATTR is `{ { editable | noneditable } | TBD }'.
The `-var-evaluate-expression' Command
--------------------------------------
Synopsis
........
-var-evaluate-expression NAME
Evaluates the expression that is represented by the specified
variable object and returns its value as a string. The format of the
string can be changed using the `-var-set-format' command.
value=VALUE
Note that one must invoke `-var-list-children' for a variable before
the value of a child variable can be evaluated.
The `-var-assign' Command
-------------------------
Synopsis
........
-var-assign NAME EXPRESSION
Assigns the value of EXPRESSION to the variable object specified by
NAME. The object must be `editable'. If the variable's value is
altered by the assign, the variable will show up in any subsequent
`-var-update' list.
Example
.......
(gdb)
-var-assign var1 3
^done,value="3"
(gdb)
-var-update *
^done,changelist=[{name="var1",in_scope="true",type_changed="false"}]
(gdb)
The `-var-update' Command
-------------------------
Synopsis
........
-var-update [PRINT-VALUES] {NAME | "*"}
Reevaluate the expressions corresponding to the variable object NAME
and all its direct and indirect children, and return the list of
variable objects whose values have changed; NAME must be a root
variable object. Here, "changed" means that the result of
`-var-evaluate-expression' before and after the `-var-update' is
different. If `*' is used as the variable object names, all existing
variable objects are updated, except for frozen ones (*note
-var-set-frozen::). The option PRINT-VALUES determines whether both
names and values, or just names are printed. The possible values of
this options are the same as for `-var-list-children' (*note
-var-list-children::). It is recommended to use the `--all-values'
option, to reduce the number of MI commands needed on each program stop.
Example
.......
(gdb)
-var-assign var1 3
^done,value="3"
(gdb)
-var-update --all-values var1
^done,changelist=[{name="var1",value="3",in_scope="true",
type_changed="false"}]
(gdb)
The field in_scope may take three values:
`"true"'
The variable object's current value is valid.
`"false"'
The variable object does not currently hold a valid value but it
may hold one in the future if its associated expression comes back
into scope.
`"invalid"'
The variable object no longer holds a valid value. This can occur
when the executable file being debugged has changed, either
through recompilation or by using the GDB `file' command. The
front end should normally choose to delete these variable objects.
In the future new values may be added to this list so the front
should be prepared for this possibility. *Note GDB/MI Development and
Front Ends: GDB/MI Development and Front Ends.
The `-var-set-frozen' Command
-----------------------------
Synopsis
........
-var-set-frozen NAME FLAG
Set the frozenness flag on the variable object NAME. The FLAG
parameter should be either `1' to make the variable frozen or `0' to
make it unfrozen. If a variable object is frozen, then neither itself,
nor any of its children, are implicitly updated by `-var-update' of a
parent variable or by `-var-update *'. Only `-var-update' of the
variable itself will update its value and values of its children.
After a variable object is unfrozen, it is implicitly updated by all
subsequent `-var-update' operations. Unfreezing a variable does not
update it, only subsequent `-var-update' does.
Example
.......
(gdb)
-var-set-frozen V 1
^done
(gdb)

File: gdb.info, Node: GDB/MI Data Manipulation, Next: GDB/MI Tracepoint Commands, Prev: GDB/MI Variable Objects, Up: GDB/MI
24.13 GDB/MI Data Manipulation
==============================
This section describes the GDB/MI commands that manipulate data:
examine memory and registers, evaluate expressions, etc.
The `-data-disassemble' Command
-------------------------------
Synopsis
........
-data-disassemble
[ -s START-ADDR -e END-ADDR ]
| [ -f FILENAME -l LINENUM [ -n LINES ] ]
-- MODE
Where:
`START-ADDR'
is the beginning address (or `$pc')
`END-ADDR'
is the end address
`FILENAME'
is the name of the file to disassemble
`LINENUM'
is the line number to disassemble around
`LINES'
is the number of disassembly lines to be produced. If it is -1,
the whole function will be disassembled, in case no END-ADDR is
specified. If END-ADDR is specified as a non-zero value, and
LINES is lower than the number of disassembly lines between
START-ADDR and END-ADDR, only LINES lines are displayed; if LINES
is higher than the number of lines between START-ADDR and
END-ADDR, only the lines up to END-ADDR are displayed.
`MODE'
is either 0 (meaning only disassembly) or 1 (meaning mixed source
and disassembly).
Result
......
The output for each instruction is composed of four fields:
* Address
* Func-name
* Offset
* Instruction
Note that whatever included in the instruction field, is not
manipulated directly by GDB/MI, i.e., it is not possible to adjust its
format.
GDB Command
...........
There's no direct mapping from this command to the CLI.
Example
.......
Disassemble from the current value of `$pc' to `$pc + 20':
(gdb)
-data-disassemble -s $pc -e "$pc + 20" -- 0
^done,
asm_insns=[
{address="0x000107c0",func-name="main",offset="4",
inst="mov 2, %o0"},
{address="0x000107c4",func-name="main",offset="8",
inst="sethi %hi(0x11800), %o2"},
{address="0x000107c8",func-name="main",offset="12",
inst="or %o2, 0x140, %o1\t! 0x11940 <_lib_version+8>"},
{address="0x000107cc",func-name="main",offset="16",
inst="sethi %hi(0x11800), %o2"},
{address="0x000107d0",func-name="main",offset="20",
inst="or %o2, 0x168, %o4\t! 0x11968 <_lib_version+48>"}]
(gdb)
Disassemble the whole `main' function. Line 32 is part of `main'.
-data-disassemble -f basics.c -l 32 -- 0
^done,asm_insns=[
{address="0x000107bc",func-name="main",offset="0",
inst="save %sp, -112, %sp"},
{address="0x000107c0",func-name="main",offset="4",
inst="mov 2, %o0"},
{address="0x000107c4",func-name="main",offset="8",
inst="sethi %hi(0x11800), %o2"},
[...]
{address="0x0001081c",func-name="main",offset="96",inst="ret "},
{address="0x00010820",func-name="main",offset="100",inst="restore "}]
(gdb)
Disassemble 3 instructions from the start of `main':
(gdb)
-data-disassemble -f basics.c -l 32 -n 3 -- 0
^done,asm_insns=[
{address="0x000107bc",func-name="main",offset="0",
inst="save %sp, -112, %sp"},
{address="0x000107c0",func-name="main",offset="4",
inst="mov 2, %o0"},
{address="0x000107c4",func-name="main",offset="8",
inst="sethi %hi(0x11800), %o2"}]
(gdb)
Disassemble 3 instructions from the start of `main' in mixed mode:
(gdb)
-data-disassemble -f basics.c -l 32 -n 3 -- 1
^done,asm_insns=[
src_and_asm_line={line="31",
file="/kwikemart/marge/ezannoni/flathead-dev/devo/gdb/ \
testsuite/gdb.mi/basics.c",line_asm_insn=[
{address="0x000107bc",func-name="main",offset="0",
inst="save %sp, -112, %sp"}]},
src_and_asm_line={line="32",
file="/kwikemart/marge/ezannoni/flathead-dev/devo/gdb/ \
testsuite/gdb.mi/basics.c",line_asm_insn=[
{address="0x000107c0",func-name="main",offset="4",
inst="mov 2, %o0"},
{address="0x000107c4",func-name="main",offset="8",
inst="sethi %hi(0x11800), %o2"}]}]
(gdb)
The `-data-evaluate-expression' Command
---------------------------------------
Synopsis
........
-data-evaluate-expression EXPR
Evaluate EXPR as an expression. The expression could contain an
inferior function call. The function call will execute synchronously.
If the expression contains spaces, it must be enclosed in double quotes.
GDB Command
...........
The corresponding GDB commands are `print', `output', and `call'. In
`gdbtk' only, there's a corresponding `gdb_eval' command.
Example
.......
In the following example, the numbers that precede the commands are the
"tokens" described in *Note GDB/MI Command Syntax: GDB/MI Command
Syntax. Notice how GDB/MI returns the same tokens in its output.
211-data-evaluate-expression A
211^done,value="1"
(gdb)
311-data-evaluate-expression &A
311^done,value="0xefffeb7c"
(gdb)
411-data-evaluate-expression A+3
411^done,value="4"
(gdb)
511-data-evaluate-expression "A + 3"
511^done,value="4"
(gdb)
The `-data-list-changed-registers' Command
------------------------------------------
Synopsis
........
-data-list-changed-registers
Display a list of the registers that have changed.
GDB Command
...........
GDB doesn't have a direct analog for this command; `gdbtk' has the
corresponding command `gdb_changed_register_list'.
Example
.......
On a PPC MBX board:
(gdb)
-exec-continue
^running
(gdb)
*stopped,reason="breakpoint-hit",bkptno="1",frame={func="main",
args=[],file="try.c",fullname="/home/foo/bar/try.c",line="5"}
(gdb)
-data-list-changed-registers
^done,changed-registers=["0","1","2","4","5","6","7","8","9",
"10","11","13","14","15","16","17","18","19","20","21","22","23",
"24","25","26","27","28","30","31","64","65","66","67","69"]
(gdb)
The `-data-list-register-names' Command
---------------------------------------
Synopsis
........
-data-list-register-names [ ( REGNO )+ ]
Show a list of register names for the current target. If no
arguments are given, it shows a list of the names of all the registers.
If integer numbers are given as arguments, it will print a list of the
names of the registers corresponding to the arguments. To ensure
consistency between a register name and its number, the output list may
include empty register names.
GDB Command
...........
GDB does not have a command which corresponds to
`-data-list-register-names'. In `gdbtk' there is a corresponding
command `gdb_regnames'.
Example
.......
For the PPC MBX board:
(gdb)
-data-list-register-names
^done,register-names=["r0","r1","r2","r3","r4","r5","r6","r7",
"r8","r9","r10","r11","r12","r13","r14","r15","r16","r17","r18",
"r19","r20","r21","r22","r23","r24","r25","r26","r27","r28","r29",
"r30","r31","f0","f1","f2","f3","f4","f5","f6","f7","f8","f9",
"f10","f11","f12","f13","f14","f15","f16","f17","f18","f19","f20",
"f21","f22","f23","f24","f25","f26","f27","f28","f29","f30","f31",
"", "pc","ps","cr","lr","ctr","xer"]
(gdb)
-data-list-register-names 1 2 3
^done,register-names=["r1","r2","r3"]
(gdb)
The `-data-list-register-values' Command
----------------------------------------
Synopsis
........
-data-list-register-values FMT [ ( REGNO )*]
Display the registers' contents. FMT is the format according to
which the registers' contents are to be returned, followed by an
optional list of numbers specifying the registers to display. A
missing list of numbers indicates that the contents of all the
registers must be returned.
Allowed formats for FMT are:
`x'
Hexadecimal
`o'
Octal
`t'
Binary
`d'
Decimal
`r'
Raw
`N'
Natural
GDB Command
...........
The corresponding GDB commands are `info reg', `info all-reg', and (in
`gdbtk') `gdb_fetch_registers'.
Example
.......
For a PPC MBX board (note: line breaks are for readability only, they
don't appear in the actual output):
(gdb)
-data-list-register-values r 64 65
^done,register-values=[{number="64",value="0xfe00a300"},
{number="65",value="0x00029002"}]
(gdb)
-data-list-register-values x
^done,register-values=[{number="0",value="0xfe0043c8"},
{number="1",value="0x3fff88"},{number="2",value="0xfffffffe"},
{number="3",value="0x0"},{number="4",value="0xa"},
{number="5",value="0x3fff68"},{number="6",value="0x3fff58"},
{number="7",value="0xfe011e98"},{number="8",value="0x2"},
{number="9",value="0xfa202820"},{number="10",value="0xfa202808"},
{number="11",value="0x1"},{number="12",value="0x0"},
{number="13",value="0x4544"},{number="14",value="0xffdfffff"},
{number="15",value="0xffffffff"},{number="16",value="0xfffffeff"},
{number="17",value="0xefffffed"},{number="18",value="0xfffffffe"},
{number="19",value="0xffffffff"},{number="20",value="0xffffffff"},
{number="21",value="0xffffffff"},{number="22",value="0xfffffff7"},
{number="23",value="0xffffffff"},{number="24",value="0xffffffff"},
{number="25",value="0xffffffff"},{number="26",value="0xfffffffb"},
{number="27",value="0xffffffff"},{number="28",value="0xf7bfffff"},
{number="29",value="0x0"},{number="30",value="0xfe010000"},
{number="31",value="0x0"},{number="32",value="0x0"},
{number="33",value="0x0"},{number="34",value="0x0"},
{number="35",value="0x0"},{number="36",value="0x0"},
{number="37",value="0x0"},{number="38",value="0x0"},
{number="39",value="0x0"},{number="40",value="0x0"},
{number="41",value="0x0"},{number="42",value="0x0"},
{number="43",value="0x0"},{number="44",value="0x0"},
{number="45",value="0x0"},{number="46",value="0x0"},
{number="47",value="0x0"},{number="48",value="0x0"},
{number="49",value="0x0"},{number="50",value="0x0"},
{number="51",value="0x0"},{number="52",value="0x0"},
{number="53",value="0x0"},{number="54",value="0x0"},
{number="55",value="0x0"},{number="56",value="0x0"},
{number="57",value="0x0"},{number="58",value="0x0"},
{number="59",value="0x0"},{number="60",value="0x0"},
{number="61",value="0x0"},{number="62",value="0x0"},
{number="63",value="0x0"},{number="64",value="0xfe00a300"},
{number="65",value="0x29002"},{number="66",value="0x202f04b5"},
{number="67",value="0xfe0043b0"},{number="68",value="0xfe00b3e4"},
{number="69",value="0x20002b03"}]
(gdb)
The `-data-read-memory' Command
-------------------------------
Synopsis
........
-data-read-memory [ -o BYTE-OFFSET ]
ADDRESS WORD-FORMAT WORD-SIZE
NR-ROWS NR-COLS [ ASCHAR ]
where:
`ADDRESS'
An expression specifying the address of the first memory word to be
read. Complex expressions containing embedded white space should
be quoted using the C convention.
`WORD-FORMAT'
The format to be used to print the memory words. The notation is
the same as for GDB's `print' command (*note Output Formats:
Output Formats.).
`WORD-SIZE'
The size of each memory word in bytes.
`NR-ROWS'
The number of rows in the output table.
`NR-COLS'
The number of columns in the output table.
`ASCHAR'
If present, indicates that each row should include an ASCII dump.
The value of ASCHAR is used as a padding character when a byte is
not a member of the printable ASCII character set (printable ASCII
characters are those whose code is between 32 and 126,
inclusively).
`BYTE-OFFSET'
An offset to add to the ADDRESS before fetching memory.
This command displays memory contents as a table of NR-ROWS by
NR-COLS words, each word being WORD-SIZE bytes. In total, `NR-ROWS *
NR-COLS * WORD-SIZE' bytes are read (returned as `total-bytes').
Should less than the requested number of bytes be returned by the
target, the missing words are identified using `N/A'. The number of
bytes read from the target is returned in `nr-bytes' and the starting
address used to read memory in `addr'.
The address of the next/previous row or page is available in
`next-row' and `prev-row', `next-page' and `prev-page'.
GDB Command
...........
The corresponding GDB command is `x'. `gdbtk' has `gdb_get_mem' memory
read command.
Example
.......
Read six bytes of memory starting at `bytes+6' but then offset by `-6'
bytes. Format as three rows of two columns. One byte per word.
Display each word in hex.
(gdb)
9-data-read-memory -o -6 -- bytes+6 x 1 3 2
9^done,addr="0x00001390",nr-bytes="6",total-bytes="6",
next-row="0x00001396",prev-row="0x0000138e",next-page="0x00001396",
prev-page="0x0000138a",memory=[
{addr="0x00001390",data=["0x00","0x01"]},
{addr="0x00001392",data=["0x02","0x03"]},
{addr="0x00001394",data=["0x04","0x05"]}]
(gdb)
Read two bytes of memory starting at address `shorts + 64' and
display as a single word formatted in decimal.
(gdb)
5-data-read-memory shorts+64 d 2 1 1
5^done,addr="0x00001510",nr-bytes="2",total-bytes="2",
next-row="0x00001512",prev-row="0x0000150e",
next-page="0x00001512",prev-page="0x0000150e",memory=[
{addr="0x00001510",data=["128"]}]
(gdb)
Read thirty two bytes of memory starting at `bytes+16' and format as
eight rows of four columns. Include a string encoding with `x' used as
the non-printable character.
(gdb)
4-data-read-memory bytes+16 x 1 8 4 x
4^done,addr="0x000013a0",nr-bytes="32",total-bytes="32",
next-row="0x000013c0",prev-row="0x0000139c",
next-page="0x000013c0",prev-page="0x00001380",memory=[
{addr="0x000013a0",data=["0x10","0x11","0x12","0x13"],ascii="xxxx"},
{addr="0x000013a4",data=["0x14","0x15","0x16","0x17"],ascii="xxxx"},
{addr="0x000013a8",data=["0x18","0x19","0x1a","0x1b"],ascii="xxxx"},
{addr="0x000013ac",data=["0x1c","0x1d","0x1e","0x1f"],ascii="xxxx"},
{addr="0x000013b0",data=["0x20","0x21","0x22","0x23"],ascii=" !\"#"},
{addr="0x000013b4",data=["0x24","0x25","0x26","0x27"],ascii="$%&'"},
{addr="0x000013b8",data=["0x28","0x29","0x2a","0x2b"],ascii="()*+"},
{addr="0x000013bc",data=["0x2c","0x2d","0x2e","0x2f"],ascii=",-./"}]
(gdb)

File: gdb.info, Node: GDB/MI Tracepoint Commands, Next: GDB/MI Symbol Query, Prev: GDB/MI Data Manipulation, Up: GDB/MI
24.14 GDB/MI Tracepoint Commands
================================
The tracepoint commands are not yet implemented.

File: gdb.info, Node: GDB/MI Symbol Query, Next: GDB/MI File Commands, Prev: GDB/MI Tracepoint Commands, Up: GDB/MI
24.15 GDB/MI Symbol Query Commands
==================================
The `-symbol-info-address' Command
----------------------------------
Synopsis
........
-symbol-info-address SYMBOL
Describe where SYMBOL is stored.
GDB Command
...........
The corresponding GDB command is `info address'.
Example
.......
N.A.
The `-symbol-info-file' Command
-------------------------------
Synopsis
........
-symbol-info-file
Show the file for the symbol.
GDB Command
...........
There's no equivalent GDB command. `gdbtk' has `gdb_find_file'.
Example
.......
N.A.
The `-symbol-info-function' Command
-----------------------------------
Synopsis
........
-symbol-info-function
Show which function the symbol lives in.
GDB Command
...........
`gdb_get_function' in `gdbtk'.
Example
.......
N.A.
The `-symbol-info-line' Command
-------------------------------
Synopsis
........
-symbol-info-line
Show the core addresses of the code for a source line.
GDB Command
...........
The corresponding GDB command is `info line'. `gdbtk' has the
`gdb_get_line' and `gdb_get_file' commands.
Example
.......
N.A.
The `-symbol-info-symbol' Command
---------------------------------
Synopsis
........
-symbol-info-symbol ADDR
Describe what symbol is at location ADDR.
GDB Command
...........
The corresponding GDB command is `info symbol'.
Example
.......
N.A.
The `-symbol-list-functions' Command
------------------------------------
Synopsis
........
-symbol-list-functions
List the functions in the executable.
GDB Command
...........
`info functions' in GDB, `gdb_listfunc' and `gdb_search' in `gdbtk'.
Example
.......
N.A.
The `-symbol-list-lines' Command
--------------------------------
Synopsis
........
-symbol-list-lines FILENAME
Print the list of lines that contain code and their associated
program addresses for the given source filename. The entries are
sorted in ascending PC order.
GDB Command
...........
There is no corresponding GDB command.
Example
.......
(gdb)
-symbol-list-lines basics.c
^done,lines=[{pc="0x08048554",line="7"},{pc="0x0804855a",line="8"}]
(gdb)
The `-symbol-list-types' Command
--------------------------------
Synopsis
........
-symbol-list-types
List all the type names.
GDB Command
...........
The corresponding commands are `info types' in GDB, `gdb_search' in
`gdbtk'.
Example
.......
N.A.
The `-symbol-list-variables' Command
------------------------------------
Synopsis
........
-symbol-list-variables
List all the global and static variable names.
GDB Command
...........
`info variables' in GDB, `gdb_search' in `gdbtk'.
Example
.......
N.A.
The `-symbol-locate' Command
----------------------------
Synopsis
........
-symbol-locate
GDB Command
...........
`gdb_loc' in `gdbtk'.
Example
.......
N.A.
The `-symbol-type' Command
--------------------------
Synopsis
........
-symbol-type VARIABLE
Show type of VARIABLE.
GDB Command
...........
The corresponding GDB command is `ptype', `gdbtk' has
`gdb_obj_variable'.
Example
.......
N.A.

File: gdb.info, Node: GDB/MI File Commands, Next: GDB/MI Target Manipulation, Prev: GDB/MI Symbol Query, Up: GDB/MI
24.16 GDB/MI File Commands
==========================
This section describes the GDB/MI commands to specify executable file
names and to read in and obtain symbol table information.
The `-file-exec-and-symbols' Command
------------------------------------
Synopsis
........
-file-exec-and-symbols FILE
Specify the executable file to be debugged. This file is the one
from which the symbol table is also read. If no file is specified, the
command clears the executable and symbol information. If breakpoints
are set when using this command with no arguments, GDB will produce
error messages. Otherwise, no output is produced, except a completion
notification.
GDB Command
...........
The corresponding GDB command is `file'.
Example
.......
(gdb)
-file-exec-and-symbols /kwikemart/marge/ezannoni/TRUNK/mbx/hello.mbx
^done
(gdb)
The `-file-exec-file' Command
-----------------------------
Synopsis
........
-file-exec-file FILE
Specify the executable file to be debugged. Unlike
`-file-exec-and-symbols', the symbol table is _not_ read from this
file. If used without argument, GDB clears the information about the
executable file. No output is produced, except a completion
notification.
GDB Command
...........
The corresponding GDB command is `exec-file'.
Example
.......
(gdb)
-file-exec-file /kwikemart/marge/ezannoni/TRUNK/mbx/hello.mbx
^done
(gdb)
The `-file-list-exec-sections' Command
--------------------------------------
Synopsis
........
-file-list-exec-sections
List the sections of the current executable file.
GDB Command
...........
The GDB command `info file' shows, among the rest, the same information
as this command. `gdbtk' has a corresponding command `gdb_load_info'.
Example
.......
N.A.
The `-file-list-exec-source-file' Command
-----------------------------------------
Synopsis
........
-file-list-exec-source-file
List the line number, the current source file, and the absolute path
to the current source file for the current executable. The macro
information field has a value of `1' or `0' depending on whether or not
the file includes preprocessor macro information.
GDB Command
...........
The GDB equivalent is `info source'
Example
.......
(gdb)
123-file-list-exec-source-file
123^done,line="1",file="foo.c",fullname="/home/bar/foo.c,macro-info="1"
(gdb)
The `-file-list-exec-source-files' Command
------------------------------------------
Synopsis
........
-file-list-exec-source-files
List the source files for the current executable.
It will always output the filename, but only when GDB can find the
absolute file name of a source file, will it output the fullname.
GDB Command
...........
The GDB equivalent is `info sources'. `gdbtk' has an analogous command
`gdb_listfiles'.
Example
.......
(gdb)
-file-list-exec-source-files
^done,files=[
{file=foo.c,fullname=/home/foo.c},
{file=/home/bar.c,fullname=/home/bar.c},
{file=gdb_could_not_find_fullpath.c}]
(gdb)
The `-file-list-shared-libraries' Command
-----------------------------------------
Synopsis
........
-file-list-shared-libraries
List the shared libraries in the program.
GDB Command
...........
The corresponding GDB command is `info shared'.
Example
.......
N.A.
The `-file-list-symbol-files' Command
-------------------------------------
Synopsis
........
-file-list-symbol-files
List symbol files.
GDB Command
...........
The corresponding GDB command is `info file' (part of it).
Example
.......
N.A.
The `-file-symbol-file' Command
-------------------------------
Synopsis
........
-file-symbol-file FILE
Read symbol table info from the specified FILE argument. When used
without arguments, clears GDB's symbol table info. No output is
produced, except for a completion notification.
GDB Command
...........
The corresponding GDB command is `symbol-file'.
Example
.......
(gdb)
-file-symbol-file /kwikemart/marge/ezannoni/TRUNK/mbx/hello.mbx
^done
(gdb)

File: gdb.info, Node: GDB/MI Target Manipulation, Next: GDB/MI File Transfer Commands, Prev: GDB/MI File Commands, Up: GDB/MI
24.17 GDB/MI Target Manipulation Commands
=========================================
The `-target-attach' Command
----------------------------
Synopsis
........
-target-attach PID | FILE
Attach to a process PID or a file FILE outside of GDB.
GDB Command
...........
The corresponding GDB command is `attach'.
Example
.......
N.A.
The `-target-compare-sections' Command
--------------------------------------
Synopsis
........
-target-compare-sections [ SECTION ]
Compare data of section SECTION on target to the exec file. Without
the argument, all sections are compared.
GDB Command
...........
The GDB equivalent is `compare-sections'.
Example
.......
N.A.
The `-target-detach' Command
----------------------------
Synopsis
........
-target-detach
Detach from the remote target which normally resumes its execution.
There's no output.
GDB Command
...........
The corresponding GDB command is `detach'.
Example
.......
(gdb)
-target-detach
^done
(gdb)
The `-target-disconnect' Command
--------------------------------
Synopsis
........
-target-disconnect
Disconnect from the remote target. There's no output and the target
is generally not resumed.
GDB Command
...........
The corresponding GDB command is `disconnect'.
Example
.......
(gdb)
-target-disconnect
^done
(gdb)
The `-target-download' Command
------------------------------
Synopsis
........
-target-download
Loads the executable onto the remote target. It prints out an
update message every half second, which includes the fields:
`section'
The name of the section.
`section-sent'
The size of what has been sent so far for that section.
`section-size'
The size of the section.
`total-sent'
The total size of what was sent so far (the current and the
previous sections).
`total-size'
The size of the overall executable to download.
Each message is sent as status record (*note GDB/MI Output Syntax:
GDB/MI Output Syntax.).
In addition, it prints the name and size of the sections, as they are
downloaded. These messages include the following fields:
`section'
The name of the section.
`section-size'
The size of the section.
`total-size'
The size of the overall executable to download.
At the end, a summary is printed.
GDB Command
...........
The corresponding GDB command is `load'.
Example
.......
Note: each status message appears on a single line. Here the messages
have been broken down so that they can fit onto a page.
(gdb)
-target-download
+download,{section=".text",section-size="6668",total-size="9880"}
+download,{section=".text",section-sent="512",section-size="6668",
total-sent="512",total-size="9880"}
+download,{section=".text",section-sent="1024",section-size="6668",
total-sent="1024",total-size="9880"}
+download,{section=".text",section-sent="1536",section-size="6668",
total-sent="1536",total-size="9880"}
+download,{section=".text",section-sent="2048",section-size="6668",
total-sent="2048",total-size="9880"}
+download,{section=".text",section-sent="2560",section-size="6668",
total-sent="2560",total-size="9880"}
+download,{section=".text",section-sent="3072",section-size="6668",
total-sent="3072",total-size="9880"}
+download,{section=".text",section-sent="3584",section-size="6668",
total-sent="3584",total-size="9880"}
+download,{section=".text",section-sent="4096",section-size="6668",
total-sent="4096",total-size="9880"}
+download,{section=".text",section-sent="4608",section-size="6668",
total-sent="4608",total-size="9880"}
+download,{section=".text",section-sent="5120",section-size="6668",
total-sent="5120",total-size="9880"}
+download,{section=".text",section-sent="5632",section-size="6668",
total-sent="5632",total-size="9880"}
+download,{section=".text",section-sent="6144",section-size="6668",
total-sent="6144",total-size="9880"}
+download,{section=".text",section-sent="6656",section-size="6668",
total-sent="6656",total-size="9880"}
+download,{section=".init",section-size="28",total-size="9880"}
+download,{section=".fini",section-size="28",total-size="9880"}
+download,{section=".data",section-size="3156",total-size="9880"}
+download,{section=".data",section-sent="512",section-size="3156",
total-sent="7236",total-size="9880"}
+download,{section=".data",section-sent="1024",section-size="3156",
total-sent="7748",total-size="9880"}
+download,{section=".data",section-sent="1536",section-size="3156",
total-sent="8260",total-size="9880"}
+download,{section=".data",section-sent="2048",section-size="3156",
total-sent="8772",total-size="9880"}
+download,{section=".data",section-sent="2560",section-size="3156",
total-sent="9284",total-size="9880"}
+download,{section=".data",section-sent="3072",section-size="3156",
total-sent="9796",total-size="9880"}
^done,address="0x10004",load-size="9880",transfer-rate="6586",
write-rate="429"
(gdb)
The `-target-exec-status' Command
---------------------------------
Synopsis
........
-target-exec-status
Provide information on the state of the target (whether it is
running or not, for instance).
GDB Command
...........
There's no equivalent GDB command.
Example
.......
N.A.
The `-target-list-available-targets' Command
--------------------------------------------
Synopsis
........
-target-list-available-targets
List the possible targets to connect to.
GDB Command
...........
The corresponding GDB command is `help target'.
Example
.......
N.A.
The `-target-list-current-targets' Command
------------------------------------------
Synopsis
........
-target-list-current-targets
Describe the current target.
GDB Command
...........
The corresponding information is printed by `info file' (among other
things).
Example
.......
N.A.
The `-target-list-parameters' Command
-------------------------------------
Synopsis
........
-target-list-parameters
GDB Command
...........
No equivalent.
Example
.......
N.A.
The `-target-select' Command
----------------------------
Synopsis
........
-target-select TYPE PARAMETERS ...
Connect GDB to the remote target. This command takes two args:
`TYPE'
The type of target, for instance `async', `remote', etc.
`PARAMETERS'
Device names, host names and the like. *Note Commands for
Managing Targets: Target Commands, for more details.
The output is a connection notification, followed by the address at
which the target program is, in the following form:
^connected,addr="ADDRESS",func="FUNCTION NAME",
args=[ARG LIST]
GDB Command
...........
The corresponding GDB command is `target'.
Example
.......
(gdb)
-target-select async /dev/ttya
^connected,addr="0xfe00a300",func="??",args=[]
(gdb)

File: gdb.info, Node: GDB/MI File Transfer Commands, Next: GDB/MI Miscellaneous Commands, Prev: GDB/MI Target Manipulation, Up: GDB/MI
24.18 GDB/MI File Transfer Commands
===================================
The `-target-file-put' Command
------------------------------
Synopsis
........
-target-file-put HOSTFILE TARGETFILE
Copy file HOSTFILE from the host system (the machine running GDB) to
TARGETFILE on the target system.
GDB Command
...........
The corresponding GDB command is `remote put'.
Example
.......
(gdb)
-target-file-put localfile remotefile
^done
(gdb)
The `-target-file-put' Command
------------------------------
Synopsis
........
-target-file-get TARGETFILE HOSTFILE
Copy file TARGETFILE from the target system to HOSTFILE on the host
system.
GDB Command
...........
The corresponding GDB command is `remote get'.
Example
.......
(gdb)
-target-file-get remotefile localfile
^done
(gdb)
The `-target-file-delete' Command
---------------------------------
Synopsis
........
-target-file-delete TARGETFILE
Delete TARGETFILE from the target system.
GDB Command
...........
The corresponding GDB command is `remote delete'.
Example
.......
(gdb)
-target-file-delete remotefile
^done
(gdb)

File: gdb.info, Node: GDB/MI Miscellaneous Commands, Prev: GDB/MI File Transfer Commands, Up: GDB/MI
24.19 Miscellaneous GDB/MI Commands
===================================
The `-gdb-exit' Command
-----------------------
Synopsis
........
-gdb-exit
Exit GDB immediately.
GDB Command
...........
Approximately corresponds to `quit'.
Example
.......
(gdb)
-gdb-exit
^exit
The `-exec-abort' Command
-------------------------
Synopsis
........
-exec-abort
Kill the inferior running program.
GDB Command
...........
The corresponding GDB command is `kill'.
Example
.......
N.A.
The `-gdb-set' Command
----------------------
Synopsis
........
-gdb-set
Set an internal GDB variable.
GDB Command
...........
The corresponding GDB command is `set'.
Example
.......
(gdb)
-gdb-set $foo=3
^done
(gdb)
The `-gdb-show' Command
-----------------------
Synopsis
........
-gdb-show
Show the current value of a GDB variable.
GDB Command
...........
The corresponding GDB command is `show'.
Example
.......
(gdb)
-gdb-show annotate
^done,value="0"
(gdb)
The `-gdb-version' Command
--------------------------
Synopsis
........
-gdb-version
Show version information for GDB. Used mostly in testing.
GDB Command
...........
The GDB equivalent is `show version'. GDB by default shows this
information when you start an interactive session.
Example
.......
(gdb)
-gdb-version
~GNU gdb 5.2.1
~Copyright 2000 Free Software Foundation, Inc.
~GDB is free software, covered by the GNU General Public License, and
~you are welcome to change it and/or distribute copies of it under
~ certain conditions.
~Type "show copying" to see the conditions.
~There is absolutely no warranty for GDB. Type "show warranty" for
~ details.
~This GDB was configured as
"--host=sparc-sun-solaris2.5.1 --target=ppc-eabi".
^done
(gdb)
The `-list-features' Command
----------------------------
Returns a list of particular features of the MI protocol that this
version of gdb implements. A feature can be a command, or a new field
in an output of some command, or even an important bugfix. While a
frontend can sometimes detect presence of a feature at runtime, it is
easier to perform detection at debugger startup.
The command returns a list of strings, with each string naming an
available feature. Each returned string is just a name, it does not
have any internal structure. The list of possible feature names is
given below.
Example output:
(gdb) -list-features
^done,result=["feature1","feature2"]
The current list of features is:
- `frozen-varobjs'--indicates presence of the `-var-set-frozen'
command, as well as possible presense of the `frozen' field in the
output of `-varobj-create'.
- `pending-breakpoints'--indicates presence of the `-f' option to
the `-break-insert' command.
The `-interpreter-exec' Command
-------------------------------
Synopsis
--------
-interpreter-exec INTERPRETER COMMAND
Execute the specified COMMAND in the given INTERPRETER.
GDB Command
-----------
The corresponding GDB command is `interpreter-exec'.
Example
-------
(gdb)
-interpreter-exec console "break main"
&"During symbol reading, couldn't parse type; debugger out of date?.\n"
&"During symbol reading, bad structure-type format.\n"
~"Breakpoint 1 at 0x8074fc6: file ../../src/gdb/main.c, line 743.\n"
^done
(gdb)
The `-inferior-tty-set' Command
-------------------------------
Synopsis
--------
-inferior-tty-set /dev/pts/1
Set terminal for future runs of the program being debugged.
GDB Command
-----------
The corresponding GDB command is `set inferior-tty' /dev/pts/1.
Example
-------
(gdb)
-inferior-tty-set /dev/pts/1
^done
(gdb)
The `-inferior-tty-show' Command
--------------------------------
Synopsis
--------
-inferior-tty-show
Show terminal for future runs of program being debugged.
GDB Command
-----------
The corresponding GDB command is `show inferior-tty'.
Example
-------
(gdb)
-inferior-tty-set /dev/pts/1
^done
(gdb)
-inferior-tty-show
^done,inferior_tty_terminal="/dev/pts/1"
(gdb)
The `-enable-timings' Command
-----------------------------
Synopsis
--------
-enable-timings [yes | no]
Toggle the printing of the wallclock, user and system times for an MI
command as a field in its output. This command is to help frontend
developers optimize the performance of their code. No argument is
equivalent to `yes'.
GDB Command
-----------
No equivalent.
Example
-------
(gdb)
-enable-timings
^done
(gdb)
-break-insert main
^done,bkpt={number="1",type="breakpoint",disp="keep",enabled="y",
addr="0x080484ed",func="main",file="myprog.c",
fullname="/home/nickrob/myprog.c",line="73",times="0"},
time={wallclock="0.05185",user="0.00800",system="0.00000"}
(gdb)
-enable-timings no
^done
(gdb)
-exec-run
^running
(gdb)
*stopped,reason="breakpoint-hit",bkptno="1",thread-id="0",
frame={addr="0x080484ed",func="main",args=[{name="argc",value="1"},
{name="argv",value="0xbfb60364"}],file="myprog.c",
fullname="/home/nickrob/myprog.c",line="73"}
(gdb)

File: gdb.info, Node: Annotations, Next: GDB Bugs, Prev: GDB/MI, Up: Top
25 GDB Annotations
******************
This chapter describes annotations in GDB. Annotations were designed
to interface GDB to graphical user interfaces or other similar programs
which want to interact with GDB at a relatively high level.
The annotation mechanism has largely been superseded by GDB/MI
(*note GDB/MI::).
* Menu:
* Annotations Overview:: What annotations are; the general syntax.
* Server Prefix:: Issuing a command without affecting user state.
* Prompting:: Annotations marking GDB's need for input.
* Errors:: Annotations for error messages.
* Invalidation:: Some annotations describe things now invalid.
* Annotations for Running::
Whether the program is running, how it stopped, etc.
* Source Annotations:: Annotations describing source code.

File: gdb.info, Node: Annotations Overview, Next: Server Prefix, Up: Annotations
25.1 What is an Annotation?
===========================
Annotations start with a newline character, two `control-z' characters,
and the name of the annotation. If there is no additional information
associated with this annotation, the name of the annotation is followed
immediately by a newline. If there is additional information, the name
of the annotation is followed by a space, the additional information,
and a newline. The additional information cannot contain newline
characters.
Any output not beginning with a newline and two `control-z'
characters denotes literal output from GDB. Currently there is no need
for GDB to output a newline followed by two `control-z' characters, but
if there was such a need, the annotations could be extended with an
`escape' annotation which means those three characters as output.
The annotation LEVEL, which is specified using the `--annotate'
command line option (*note Mode Options::), controls how much
information GDB prints together with its prompt, values of expressions,
source lines, and other types of output. Level 0 is for no
annotations, level 1 is for use when GDB is run as a subprocess of GNU
Emacs, level 3 is the maximum annotation suitable for programs that
control GDB, and level 2 annotations have been made obsolete (*note
Limitations of the Annotation Interface: (annotate)Limitations.).
`set annotate LEVEL'
The GDB command `set annotate' sets the level of annotations to
the specified LEVEL.
`show annotate'
Show the current annotation level.
This chapter describes level 3 annotations.
A simple example of starting up GDB with annotations is:
$ gdb --annotate=3
GNU gdb 6.0
Copyright 2003 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License,
and you are welcome to change it and/or distribute copies of it
under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB. Type "show warranty"
for details.
This GDB was configured as "i386-pc-linux-gnu"
^Z^Zpre-prompt
(gdb)
^Z^Zprompt
quit
^Z^Zpost-prompt
$
Here `quit' is input to GDB; the rest is output from GDB. The three
lines beginning `^Z^Z' (where `^Z' denotes a `control-z' character) are
annotations; the rest is output from GDB.

File: gdb.info, Node: Server Prefix, Next: Prompting, Prev: Annotations Overview, Up: Annotations
25.2 The Server Prefix
======================
If you prefix a command with `server ' then it will not affect the
command history, nor will it affect GDB's notion of which command to
repeat if <RET> is pressed on a line by itself. This means that
commands can be run behind a user's back by a front-end in a
transparent manner.
The server prefix does not affect the recording of values into the
value history; to print a value without recording it into the value
history, use the `output' command instead of the `print' command.

File: gdb.info, Node: Prompting, Next: Errors, Prev: Server Prefix, Up: Annotations
25.3 Annotation for GDB Input
=============================
When GDB prompts for input, it annotates this fact so it is possible to
know when to send output, when the output from a given command is over,
etc.
Different kinds of input each have a different "input type". Each
input type has three annotations: a `pre-' annotation, which denotes
the beginning of any prompt which is being output, a plain annotation,
which denotes the end of the prompt, and then a `post-' annotation
which denotes the end of any echo which may (or may not) be associated
with the input. For example, the `prompt' input type features the
following annotations:
^Z^Zpre-prompt
^Z^Zprompt
^Z^Zpost-prompt
The input types are
`prompt'
When GDB is prompting for a command (the main GDB prompt).
`commands'
When GDB prompts for a set of commands, like in the `commands'
command. The annotations are repeated for each command which is
input.
`overload-choice'
When GDB wants the user to select between various overloaded
functions.
`query'
When GDB wants the user to confirm a potentially dangerous
operation.
`prompt-for-continue'
When GDB is asking the user to press return to continue. Note:
Don't expect this to work well; instead use `set height 0' to
disable prompting. This is because the counting of lines is buggy
in the presence of annotations.

File: gdb.info, Node: Errors, Next: Invalidation, Prev: Prompting, Up: Annotations
25.4 Errors
===========
^Z^Zquit
This annotation occurs right before GDB responds to an interrupt.
^Z^Zerror
This annotation occurs right before GDB responds to an error.
Quit and error annotations indicate that any annotations which GDB
was in the middle of may end abruptly. For example, if a
`value-history-begin' annotation is followed by a `error', one cannot
expect to receive the matching `value-history-end'. One cannot expect
not to receive it either, however; an error annotation does not
necessarily mean that GDB is immediately returning all the way to the
top level.
A quit or error annotation may be preceded by
^Z^Zerror-begin
Any output between that and the quit or error annotation is the error
message.
Warning messages are not yet annotated.

File: gdb.info, Node: Invalidation, Next: Annotations for Running, Prev: Errors, Up: Annotations
25.5 Invalidation Notices
=========================
The following annotations say that certain pieces of state may have
changed.
`^Z^Zframes-invalid'
The frames (for example, output from the `backtrace' command) may
have changed.
`^Z^Zbreakpoints-invalid'
The breakpoints may have changed. For example, the user just
added or deleted a breakpoint.

File: gdb.info, Node: Annotations for Running, Next: Source Annotations, Prev: Invalidation, Up: Annotations
25.6 Running the Program
========================
When the program starts executing due to a GDB command such as `step'
or `continue',
^Z^Zstarting
is output. When the program stops,
^Z^Zstopped
is output. Before the `stopped' annotation, a variety of
annotations describe how the program stopped.
`^Z^Zexited EXIT-STATUS'
The program exited, and EXIT-STATUS is the exit status (zero for
successful exit, otherwise nonzero).
`^Z^Zsignalled'
The program exited with a signal. After the `^Z^Zsignalled', the
annotation continues:
INTRO-TEXT
^Z^Zsignal-name
NAME
^Z^Zsignal-name-end
MIDDLE-TEXT
^Z^Zsignal-string
STRING
^Z^Zsignal-string-end
END-TEXT
where NAME is the name of the signal, such as `SIGILL' or
`SIGSEGV', and STRING is the explanation of the signal, such as
`Illegal Instruction' or `Segmentation fault'. INTRO-TEXT,
MIDDLE-TEXT, and END-TEXT are for the user's benefit and have no
particular format.
`^Z^Zsignal'
The syntax of this annotation is just like `signalled', but GDB is
just saying that the program received the signal, not that it was
terminated with it.
`^Z^Zbreakpoint NUMBER'
The program hit breakpoint number NUMBER.
`^Z^Zwatchpoint NUMBER'
The program hit watchpoint number NUMBER.

File: gdb.info, Node: Source Annotations, Prev: Annotations for Running, Up: Annotations
25.7 Displaying Source
======================
The following annotation is used instead of displaying source code:
^Z^Zsource FILENAME:LINE:CHARACTER:MIDDLE:ADDR
where FILENAME is an absolute file name indicating which source
file, LINE is the line number within that file (where 1 is the first
line in the file), CHARACTER is the character position within the file
(where 0 is the first character in the file) (for most debug formats
this will necessarily point to the beginning of a line), MIDDLE is
`middle' if ADDR is in the middle of the line, or `beg' if ADDR is at
the beginning of the line, and ADDR is the address in the target
program associated with the source which is being displayed. ADDR is
in the form `0x' followed by one or more lowercase hex digits (note
that this does not depend on the language).

File: gdb.info, Node: GDB Bugs, Next: Command Line Editing, Prev: Annotations, Up: Top
26 Reporting Bugs in GDB
************************
Your bug reports play an essential role in making GDB reliable.
Reporting a bug may help you by bringing a solution to your problem,
or it may not. But in any case the principal function of a bug report
is to help the entire community by making the next version of GDB work
better. Bug reports are your contribution to the maintenance of GDB.
In order for a bug report to serve its purpose, you must include the
information that enables us to fix the bug.
* Menu:
* Bug Criteria:: Have you found a bug?
* Bug Reporting:: How to report bugs

File: gdb.info, Node: Bug Criteria, Next: Bug Reporting, Up: GDB Bugs
26.1 Have You Found a Bug?
==========================
If you are not sure whether you have found a bug, here are some
guidelines:
* If the debugger gets a fatal signal, for any input whatever, that
is a GDB bug. Reliable debuggers never crash.
* If GDB produces an error message for valid input, that is a bug.
(Note that if you're cross debugging, the problem may also be
somewhere in the connection to the target.)
* If GDB does not produce an error message for invalid input, that
is a bug. However, you should note that your idea of "invalid
input" might be our idea of "an extension" or "support for
traditional practice".
* If you are an experienced user of debugging tools, your suggestions
for improvement of GDB are welcome in any case.

File: gdb.info, Node: Bug Reporting, Prev: Bug Criteria, Up: GDB Bugs
26.2 How to Report Bugs
=======================
A number of companies and individuals offer support for GNU products.
If you obtained GDB from a support organization, we recommend you
contact that organization first.
You can find contact information for many support companies and
individuals in the file `etc/SERVICE' in the GNU Emacs distribution.
In any event, we also recommend that you submit bug reports for GDB.
The preferred method is to submit them directly using GDB's Bugs web
page (http://www.gnu.org/software/gdb/bugs/). Alternatively, the
e-mail gateway <bug-gdb@gnu.org> can be used.
*Do not send bug reports to `info-gdb', or to `help-gdb', or to any
newsgroups.* Most users of GDB do not want to receive bug reports.
Those that do have arranged to receive `bug-gdb'.
The mailing list `bug-gdb' has a newsgroup `gnu.gdb.bug' which
serves as a repeater. The mailing list and the newsgroup carry exactly
the same messages. Often people think of posting bug reports to the
newsgroup instead of mailing them. This appears to work, but it has one
problem which can be crucial: a newsgroup posting often lacks a mail
path back to the sender. Thus, if we need to ask for more information,
we may be unable to reach you. For this reason, it is better to send
bug reports to the mailing list.
The fundamental principle of reporting bugs usefully is this:
*report all the facts*. If you are not sure whether to state a 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 do not matter. Thus, you might
assume that the name of the variable you use in an example does not
matter. 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 the bug. Play it safe and give a
specific, complete example. That is the easiest thing for you to do,
and the most helpful.
Keep in mind that the purpose of a bug report is to enable us to fix
the bug. It may be that the bug has been reported previously, but
neither you nor we can know that unless your bug report is complete and
self-contained.
Sometimes people give a few sketchy facts and ask, "Does this ring a
bell?" Those bug reports are useless, and we urge everyone to _refuse
to respond to them_ except to chide the sender to report bugs properly.
To enable us to fix the bug, you should include all these things:
* The version of GDB. GDB announces it if you start with no
arguments; you can also print it at any time using `show version'.
Without this, we will not know whether there is any point in
looking for the bug in the current version of GDB.
* The type of machine you are using, and the operating system name
and version number.
* What compiler (and its version) was used to compile GDB--e.g.
"gcc-2.8.1".
* What compiler (and its version) was used to compile the program
you are debugging--e.g. "gcc-2.8.1", or "HP92453-01 A.10.32.03 HP
C Compiler". For GCC, you can say `gcc --version' to get this
information; for other compilers, see the documentation for those
compilers.
* The command arguments you gave the compiler to compile your
example and observe the bug. For example, did you use `-O'? To
guarantee you will not omit something important, list them all. A
copy of the Makefile (or the output from make) is sufficient.
If we were to try to guess the arguments, we would probably guess
wrong and then we might not encounter the bug.
* A complete input script, and all necessary source files, that will
reproduce the bug.
* A description of what behavior you observe that you believe is
incorrect. For example, "It gets a fatal signal."
Of course, if the bug is that GDB gets a fatal signal, then we
will certainly notice it. But if the bug is incorrect output, we
might not notice unless it is glaringly wrong. You might as well
not give us a chance to make a mistake.
Even if the problem you experience is a fatal signal, you should
still say so explicitly. Suppose something strange is going on,
such as, your copy of GDB is out of synch, or you have encountered
a bug in the C library on your system. (This has happened!) Your
copy might crash and ours would not. If you told us to expect a
crash, then when ours fails to crash, we would know that the bug
was not happening for us. If you had not told us to expect a
crash, then we would not be able to draw any conclusion from our
observations.
To collect all this information, you can use a session recording
program such as `script', which is available on many Unix systems.
Just run your GDB session inside `script' and then include the
`typescript' file with your bug report.
Another way to record a GDB session is to run GDB inside Emacs and
then save the entire buffer to a file.
* If you wish to suggest changes to the GDB source, send us context
diffs. If you even discuss something in the GDB source, refer to
it by context, not by line number.
The line numbers in our development sources will not match those
in your sources. Your line numbers would convey no useful
information to us.
Here are some things that are not necessary:
* A description of the envelope of the bug.
Often people who encounter a bug spend a lot of time investigating
which changes to the input file will make the bug go away and which
changes will not affect it.
This is often time consuming and not very useful, because the way
we will find the bug is by running a single example under the
debugger with breakpoints, not by pure deduction from a series of
examples. We recommend that you save your time for something else.
Of course, if you can find a simpler example to report _instead_
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, and so on.
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.
* A patch for the bug.
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 GDB it is very hard to
construct an example that will make the program follow a certain
path through the code. If you do not send us the example, we will
not be able to construct one, so we will not be able to verify
that the bug is fixed.
And if we cannot understand what bug you are trying to fix, or why
your patch should be an improvement, we will not install it. A
test case will help us to understand.
* A guess about what the bug is or what it depends on.
Such guesses are usually wrong. Even we cannot guess right about
such things without first using the debugger to find the facts.

File: gdb.info, Node: Command Line Editing, Next: Using History Interactively, Prev: GDB Bugs, Up: Top
27 Command Line Editing
***********************
This chapter describes the basic features of the GNU command line
editing interface.
* Menu:
* Introduction and Notation:: Notation used in this text.
* Readline Interaction:: The minimum set of commands for editing a line.
* Readline Init File:: Customizing Readline from a user's view.
* Bindable Readline Commands:: A description of most of the Readline commands
available for binding
* Readline vi Mode:: A short description of how to make Readline
behave like the vi editor.

File: gdb.info, Node: Introduction and Notation, Next: Readline Interaction, Up: Command Line Editing
27.1 Introduction to Line Editing
=================================
The following paragraphs describe the notation used to represent
keystrokes.
The text `C-k' is read as `Control-K' and describes the character
produced when the <k> key is pressed while the Control key is depressed.
The text `M-k' is read as `Meta-K' and describes the character
produced when the Meta key (if you have one) is depressed, and the <k>
key is pressed. The Meta key is labeled <ALT> on many keyboards. On
keyboards with two keys labeled <ALT> (usually to either side of the
space bar), the <ALT> on the left side is generally set to work as a
Meta key. The <ALT> key on the right may also be configured to work as
a Meta key or may be configured as some other modifier, such as a
Compose key for typing accented characters.
If you do not have a Meta or <ALT> key, or another key working as a
Meta key, the identical keystroke can be generated by typing <ESC>
_first_, and then typing <k>. Either process is known as "metafying"
the <k> key.
The text `M-C-k' is read as `Meta-Control-k' and describes the
character produced by "metafying" `C-k'.
In addition, several keys have their own names. Specifically,
<DEL>, <ESC>, <LFD>, <SPC>, <RET>, and <TAB> all stand for themselves
when seen in this text, or in an init file (*note Readline Init File::).
If your keyboard lacks a <LFD> key, typing <C-j> will produce the
desired character. The <RET> key may be labeled <Return> or <Enter> on
some keyboards.

File: gdb.info, Node: Readline Interaction, Next: Readline Init File, Prev: Introduction and Notation, Up: Command Line Editing
27.2 Readline Interaction
=========================
Often during an interactive session you type in a long line of text,
only to notice that the first word on the line is misspelled. The
Readline library gives you a set of commands for manipulating the text
as you type it in, allowing you to just fix your typo, and not forcing
you to retype the majority of the line. Using these editing commands,
you move the cursor to the place that needs correction, and delete or
insert the text of the corrections. Then, when you are satisfied with
the line, you simply press <RET>. You do not have to be at the end of
the line to press <RET>; the entire line is accepted regardless of the
location of the cursor within the line.
* Menu:
* Readline Bare Essentials:: The least you need to know about Readline.
* Readline Movement Commands:: Moving about the input line.
* Readline Killing Commands:: How to delete text, and how to get it back!
* Readline Arguments:: Giving numeric arguments to commands.
* Searching:: Searching through previous lines.

File: gdb.info, Node: Readline Bare Essentials, Next: Readline Movement Commands, Up: Readline Interaction
27.2.1 Readline Bare Essentials
-------------------------------
In order to enter characters into the line, simply type them. The typed
character appears where the cursor was, and then the cursor moves one
space to the right. If you mistype a character, you can use your erase
character to back up and delete the mistyped character.
Sometimes you may mistype a character, and not notice the error
until you have typed several other characters. In that case, you can
type `C-b' to move the cursor to the left, and then correct your
mistake. Afterwards, you can move the cursor to the right with `C-f'.
When you add text in the middle of a line, you will notice that
characters to the right of the cursor are `pushed over' to make room
for the text that you have inserted. Likewise, when you delete text
behind the cursor, characters to the right of the cursor are `pulled
back' to fill in the blank space created by the removal of the text. A
list of the bare essentials for editing the text of an input line
follows.
`C-b'
Move back one character.
`C-f'
Move forward one character.
<DEL> or <Backspace>
Delete the character to the left of the cursor.
`C-d'
Delete the character underneath the cursor.
Printing characters
Insert the character into the line at the cursor.
`C-_' or `C-x C-u'
Undo the last editing command. You can undo all the way back to an
empty line.
(Depending on your configuration, the <Backspace> key be set to delete
the character to the left of the cursor and the <DEL> key set to delete
the character underneath the cursor, like `C-d', rather than the
character to the left of the cursor.)

File: gdb.info, Node: Readline Movement Commands, Next: Readline Killing Commands, Prev: Readline Bare Essentials, Up: Readline Interaction
27.2.2 Readline Movement Commands
---------------------------------
The above table describes the most basic keystrokes that you need in
order to do editing of the input line. For your convenience, many
other commands have been added in addition to `C-b', `C-f', `C-d', and
<DEL>. Here are some commands for moving more rapidly about the line.
`C-a'
Move to the start of the line.
`C-e'
Move to the end of the line.
`M-f'
Move forward a word, where a word is composed of letters and
digits.
`M-b'
Move backward a word.
`C-l'
Clear the screen, reprinting the current line at the top.
Notice how `C-f' moves forward a character, while `M-f' moves
forward a word. It is a loose convention that control keystrokes
operate on characters while meta keystrokes operate on words.

File: gdb.info, Node: Readline Killing Commands, Next: Readline Arguments, Prev: Readline Movement Commands, Up: Readline Interaction
27.2.3 Readline Killing Commands
--------------------------------
"Killing" text means to delete the text from the line, but to save it
away for later use, usually by "yanking" (re-inserting) it back into
the line. (`Cut' and `paste' are more recent jargon for `kill' and
`yank'.)
If the description for a command says that it `kills' text, then you
can be sure that you can get the text back in a different (or the same)
place later.
When you use a kill command, the text is saved in a "kill-ring".
Any number of consecutive kills save all of the killed text together, so
that when you yank it back, you get it all. The kill ring is not line
specific; the text that you killed on a previously typed line is
available to be yanked back later, when you are typing another line.
Here is the list of commands for killing text.
`C-k'
Kill the text from the current cursor position to the end of the
line.
`M-d'
Kill from the cursor to the end of the current word, or, if between
words, to the end of the next word. Word boundaries are the same
as those used by `M-f'.
`M-<DEL>'
Kill from the cursor the start of the current word, or, if between
words, to the start of the previous word. Word boundaries are the
same as those used by `M-b'.
`C-w'
Kill from the cursor to the previous whitespace. This is
different than `M-<DEL>' because the word boundaries differ.
Here is how to "yank" the text back into the line. Yanking means to
copy the most-recently-killed text from the kill buffer.
`C-y'
Yank the most recently killed text back into the buffer at the
cursor.
`M-y'
Rotate the kill-ring, and yank the new top. You can only do this
if the prior command is `C-y' or `M-y'.

File: gdb.info, Node: Readline Arguments, Next: Searching, Prev: Readline Killing Commands, Up: Readline Interaction
27.2.4 Readline Arguments
-------------------------
You can pass numeric arguments to Readline commands. Sometimes the
argument acts as a repeat count, other times it is the sign of the
argument that is significant. If you pass a negative argument to a
command which normally acts in a forward direction, that command will
act in a backward direction. For example, to kill text back to the
start of the line, you might type `M-- C-k'.
The general way to pass numeric arguments to a command is to type
meta digits before the command. If the first `digit' typed is a minus
sign (`-'), then the sign of the argument will be negative. Once you
have typed one meta digit to get the argument started, you can type the
remainder of the digits, and then the command. For example, to give
the `C-d' command an argument of 10, you could type `M-1 0 C-d', which
will delete the next ten characters on the input line.

File: gdb.info, Node: Searching, Prev: Readline Arguments, Up: Readline Interaction
27.2.5 Searching for Commands in the History
--------------------------------------------
Readline provides commands for searching through the command history
for lines containing a specified string. There are two search modes:
"incremental" and "non-incremental".
Incremental searches begin before the user has finished typing the
search string. As each character of the search string is typed,
Readline displays the next entry from the history matching the string
typed so far. An incremental search requires only as many characters
as needed to find the desired history entry. To search backward in the
history for a particular string, type `C-r'. Typing `C-s' searches
forward through the history. The characters present in the value of
the `isearch-terminators' variable are used to terminate an incremental
search. If that variable has not been assigned a value, the <ESC> and
`C-J' characters will terminate an incremental search. `C-g' will
abort an incremental search and restore the original line. When the
search is terminated, the history entry containing the search string
becomes the current line.
To find other matching entries in the history list, type `C-r' or
`C-s' as appropriate. This will search backward or forward in the
history for the next entry matching the search string typed so far.
Any other key sequence bound to a Readline command will terminate the
search and execute that command. For instance, a <RET> will terminate
the search and accept the line, thereby executing the command from the
history list. A movement command will terminate the search, make the
last line found the current line, and begin editing.
Readline remembers the last incremental search string. If two
`C-r's are typed without any intervening characters defining a new
search string, any remembered search string is used.
Non-incremental searches read the entire search string before
starting to search for matching history lines. The search string may be
typed by the user or be part of the contents of the current line.

File: gdb.info, Node: Readline Init File, Next: Bindable Readline Commands, Prev: Readline Interaction, Up: Command Line Editing
27.3 Readline Init File
=======================
Although the Readline library comes with a set of Emacs-like
keybindings installed by default, it is possible to use a different set
of keybindings. Any user can customize programs that use Readline by
putting commands in an "inputrc" file, conventionally in his home
directory. The name of this file is taken from the value of the
environment variable `INPUTRC'. If that variable is unset, the default
is `~/.inputrc'.
When a program which uses the Readline library starts up, the init
file is read, and the key bindings are set.
In addition, the `C-x C-r' command re-reads this init file, thus
incorporating any changes that you might have made to it.
* Menu:
* Readline Init File Syntax:: Syntax for the commands in the inputrc file.
* Conditional Init Constructs:: Conditional key bindings in the inputrc file.
* Sample Init File:: An example inputrc file.

File: gdb.info, Node: Readline Init File Syntax, Next: Conditional Init Constructs, Up: Readline Init File
27.3.1 Readline Init File Syntax
--------------------------------
There are only a few basic constructs allowed in the Readline init
file. Blank lines are ignored. Lines beginning with a `#' are
comments. Lines beginning with a `$' indicate conditional constructs
(*note Conditional Init Constructs::). Other lines denote variable
settings and key bindings.
Variable Settings
You can modify the run-time behavior of Readline by altering the
values of variables in Readline using the `set' command within the
init file. The syntax is simple:
set VARIABLE VALUE
Here, for example, is how to change from the default Emacs-like
key binding to use `vi' line editing commands:
set editing-mode vi
Variable names and values, where appropriate, are recognized
without regard to case. Unrecognized variable names are ignored.
Boolean variables (those that can be set to on or off) are set to
on if the value is null or empty, ON (case-insensitive), or 1.
Any other value results in the variable being set to off.
A great deal of run-time behavior is changeable with the following
variables.
`bell-style'
Controls what happens when Readline wants to ring the
terminal bell. If set to `none', Readline never rings the
bell. If set to `visible', Readline uses a visible bell if
one is available. If set to `audible' (the default),
Readline attempts to ring the terminal's bell.
`bind-tty-special-chars'
If set to `on', Readline attempts to bind the control
characters treated specially by the kernel's terminal driver
to their Readline equivalents.
`comment-begin'
The string to insert at the beginning of the line when the
`insert-comment' command is executed. The default value is
`"#"'.
`completion-ignore-case'
If set to `on', Readline performs filename matching and