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### Start GDB with annotations enabled

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Annotations-Overview.html

Example of starting GDB with the --annotate=3 option, showing the startup output and the annotations (pre-prompt, prompt, post-prompt) marked by '^Z^Z'. The 'quit' line is input to GDB.

```shell
$ 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
$
```

--------------------------------

### Example of trace commands: trace, actions, tstart, tstop

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Starting-and-Stopping-Trace-Experiments.html

Shows a GDB session defining a tracepoint, setting actions to collect registers and locals, stepping, then starting and stopping the trace. The tstart command discards previous data and tstop stops collection.

```gdb
(gdb) trace gdb_c_test
(gdb) actions
Enter actions for tracepoint #1, one per line.
> collect $regs,$locals,$args
> while-stepping 11
  > collect $regs
  > end
> end
(gdb) tstart
	[time passes …]
(gdb) tstop
```

--------------------------------

### -target-download example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Target-Manipulation.html

Example of downloading an executable, showing status messages and final summary.

```gdb
(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)
```

--------------------------------

### -thread-select example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Thread-Commands.html

Example showing -thread-select usage with preceding commands and output.

```gdb
(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",arch="i386:x86_64"}
(gdb)
```

--------------------------------

### -file-exec-file example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-File-Commands.html

Example of the -file-exec-file command. Shows the command and its completion notification ^done.

```gdb
(gdb)
-file-exec-file /kwikemart/marge/ezannoni/TRUNK/mbx/hello.mbx
^done
(gdb)
```

--------------------------------

### GDB 'info trace' command output example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Listing-Tracepoints.html

Example output from the 'info trace' command showing tracepoint details including passcount, while-stepping actions, collect commands, and installation state. The output includes multiple locations for tracepoint 2 and a pending location.

```gdb
(gdb) info trace
Num     Type           Disp Enb Address    What
1       tracepoint     keep y   0x0804ab57 in foo() at main.cxx:7
        while-stepping 20
          collect globfoo, $regs
        end
        collect globfoo2
        end
        pass count 1200
2       tracepoint     keep y   <MULTIPLE>
        collect $eip
2.1                         y     0x0804859c in func4 at change-loc.h:35
        installed on target
2.2                         y     0xb7ffc480 in func4 at change-loc.h:35
        installed on target
2.3                         y     <PENDING>  set_tracepoint
3       tracepoint     keep y   0x080485b1 in foo at change-loc.c:29
        not installed on target
(gdb)
```

--------------------------------

### -complete example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example showing completion for various partial commands, including results with matches and max_completions_reached.

```gdb
(gdb)
-complete br
^done,completion="break",
      matches=["break","break-range"],
      max_completions_reached="0"
(gdb)
-complete "b ma"
^done,completion="b ma",
      matches=["b madvise","b main"],max_completions_reached="0"
(gdb)
-complete "b push_b"
^done,completion="b push_back(",
      matches=[
       "b A::push_back(void*)",
       "b std::string::push_back(char)",
       "b std::vector<int, std::allocator<int> >::push_back(int&&)"],
      max_completions_reached="0"
(gdb)
-complete "nonexist"
^done,matches=[],max_completions_reached="0"
(gdb)
```

--------------------------------

### -environment-cd example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Context.html

Example of using -environment-cd to change the working directory.

```gdb
(gdb)
-environment-cd /kwikemart/marge/ezannoni/flathead-dev/devo/gdb
^done
(gdb)
```

--------------------------------

### -gdb-version example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example of using -gdb-version, showing the version output and MI result.

```gdb
(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)
```

--------------------------------

### Start GDB on sample program

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Macros.html

Command to start GDB on the sample program, showing the GDB banner and prompt.

```shell
$ gdb -nw sample
GNU gdb 2002-05-06-cvs
Copyright 2002 Free Software Foundation, Inc.
GDB is free software, …
(gdb)
```

--------------------------------

### Start gdbserver and connect GDB to run to main

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Server.html

Start gdbserver on port 9999, then start GDB, connect to the remote target, set a breakpoint at main, and continue to load shared libraries including the in-process agent.

```shell
$ gdbserver :9999 myprogram
```

```gdb
$ gdb myprogram
(gdb) target remote myhost:9999
0x00007f215893ba60 in ?? () from /lib64/ld-linux-x86-64.so.2
(gdb) b main
(gdb) continue
```

--------------------------------

### -thread-info example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Thread-Commands.html

Example output of the -thread-info command showing thread information and current-thread-id.

```gdb
-thread-info
^done,threads=[
{id="2",target-id="Thread 0xb7e14b90 (LWP 21257)",
   frame={level="0",addr="0xffffe410",func="__kernel_vsyscall",
           args=[]},state="running"},
{id="1",target-id="Thread 0xb7e156b0 (LWP 21254)",
   frame={level="0",addr="0x0804891f",func="foo",
           args=[{name="i",value="10"}],
           file="/tmp/a.c",fullname="/tmp/a.c",line="158",arch="i386:x86_64"},
           state="running"}],
current-thread-id="1"
(gdb)
```

--------------------------------

### -file-exec-and-symbols example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-File-Commands.html

Example of the -file-exec-and-symbols command. Shows the command and its completion notification ^done.

```gdb
(gdb)
-file-exec-and-symbols /kwikemart/marge/ezannoni/TRUNK/mbx/hello.mbx
^done
(gdb)
```

--------------------------------

### -exec-run example with breakpoint

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Execution.html

Example GDB/MI session showing -exec-run stopping at a breakpoint in main.

```gdb
(gdb)
-break-insert main
^done,bkpt={number="1",addr="0x0001072c",file="recursive2.c",line="4"}
(gdb)
-exec-run
^running
(gdb)
*stopped,reason="breakpoint-hit",disp="keep",bkptno="1",
frame={func="main",args=[],file="recursive2.c",
fullname="/home/foo/bar/recursive2.c",line="4",arch="i386:x86_64"}
(gdb)
```

--------------------------------

### -environment-pwd example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Context.html

Example of using -environment-pwd to display the current working directory.

```gdb
(gdb)
-environment-pwd
^done,cwd="/kwikemart/marge/ezannoni/flathead-dev/devo/gdb"
(gdb)
```

--------------------------------

### -target-file-get example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-File-Transfer-Commands.html

Example of using -target-file-get to copy a remote file to the local host.

```gdb
(gdb)
-target-file-get remotefile localfile
^done
(gdb)
```

--------------------------------

### -environment-path example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Context.html

Example showing various uses of -environment-path, including displaying the current path, adding directories, and resetting the path.

```gdb
(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)
```

--------------------------------

### -exec-next example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Execution.html

Example GDB/MI session showing the -exec-next command and its output, stopping at line 8 of hello.c.

```gdb
-exec-next
^running
(gdb)
*stopped,reason="end-stepping-range",line="8",file="hello.c"
(gdb)
```

--------------------------------

### -environment-directory example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Context.html

Example showing various uses of -environment-directory, including adding directories, resetting the path, and displaying the current path.

```gdb
(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)
```

--------------------------------

### -stack-select-frame example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Stack-Manipulation.html

Example invocation of -stack-select-frame 2, showing a successful response.

```gdb
(gdb)
-stack-select-frame 2
^done
(gdb)
```

--------------------------------

### -exec-jump example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Execution.html

Example of -exec-jump with locspec foo.c:10, showing the *running and ^running responses.

```gdb
-exec-jump foo.c:10
*running,thread-id="all"
^running
```

--------------------------------

### -inferior-tty-show example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example of setting and then showing the inferior TTY, with the result containing inferior_tty_terminal.

```gdb
(gdb)
-inferior-tty-set /dev/pts/1
^done
(gdb)
-inferior-tty-show
^done,inferior_tty_terminal="/dev/pts/1"
(gdb)
```

--------------------------------

### -gdb-set example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example of using -gdb-set to set a variable, showing the MI output.

```gdb
(gdb)
-gdb-set $foo=3
^done
(gdb)
```

--------------------------------

### -gdb-exit example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example of using -gdb-exit to exit GDB, showing the MI output.

```gdb
(gdb)
-gdb-exit
^exit
```

--------------------------------

### Start GDB with an executable and a core file

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Invoking-GDB.html

Start GDB with both an executable program and a core file specified.

```shell
gdb program core
```

--------------------------------

### -catch-catch example with output

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/C_002b_002b-Exception-GDB_002fMI-Catchpoint-Commands.html

Example of using -catch-catch with a regexp, showing the catchpoint creation and the stop when the exception is caught.

```gdb
-catch-catch -r exception_type
^done,bkpt={number="1",type="catchpoint",disp="keep",enabled="y",
  what="exception catch",catch-type="catch",
  thread-groups=["i1"],
  regexp="exception_type",times="0"}
(gdb)
-exec-run
^running
(gdb)
~"\n"
~"Catchpoint 1 (exception caught), 0x00007ffff7ae00ed
  in __cxa_begin_catch () from /lib64/libstdc++.so.6\n"
*stopped,bkptno="1",reason="breakpoint-hit",disp="keep",
  frame={addr="0x00007ffff7ae00ed",func="__cxa_begin_catch",
  args=[],from="/lib64/libstdc++.so.6",arch="i386:x86-64"},
  thread-id="1",stopped-threads="all",core="6"
(gdb)
```

--------------------------------

### Start GDB with an executable program

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Invoking-GDB.html

The most usual way to start GDB is with one argument specifying an executable program.

```shell
gdb program
```

--------------------------------

### -list-features example output

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Support-Commands.html

Example output of the -list-features command, returning a list of feature names.

```gdb
(gdb) -list-features
^done,features=["feature1","feature2"]
```

--------------------------------

### -gdb-show example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example of using -gdb-show to display a variable value, showing the MI output.

```gdb
(gdb)
-gdb-show annotate
^done,value="0"
(gdb)
```

--------------------------------

### -break-commands example with -break-insert

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Breakpoint-Commands.html

Example showing how to attach the commands 'print v' and 'continue' to breakpoint 1.

```gdb
(gdb)
-break-insert main
^done,bkpt={number="1",type="breakpoint",disp="keep",
enabled="y",addr="0x000100d0",func="main",file="hello.c",
fullname="/home/foo/hello.c",line="5",thread-groups=["i1"],
times="0"}
(gdb)
-break-commands 1 "print v" "continue"
^done
(gdb)
```

--------------------------------

### sal-pc

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Symbol-Tables-In-Guile.html

Get the start of the address range for a sal.

```APIDOC
## sal-pc

### Description
Return the start of the address range occupied by code for sal.

### Procedure
`sal-pc sal`

### Parameters
- **sal** (<gdb:sal>) - The sal object.

### Returns
- **integer** - The start address.
```

--------------------------------

### -break-condition example with -break-list

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Breakpoint-Commands.html

Example showing how to set condition '1' on breakpoint 1 and verify it in the breakpoint list output.

```gdb
(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",thread-groups=["i1"],times="0",ignore="3"}]}
(gdb)
```

--------------------------------

### -target-flash-erase example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Target-Manipulation.html

Example of using -target-flash-erase in GDB MI. The output is a list of flash regions that have been erased, with starting addresses and memory region sizes.

```gdb
(gdb)
-target-flash-erase
^done,erased-regions={address="0x0",size="0x40000"}
(gdb)
```

--------------------------------

### QTStart

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Tracepoint-Packets.html

Begins the tracepoint experiment and starts collecting data from tracepoint hits.

```APIDOC
## QTStart

### Description
Begins the tracepoint experiment. Starts collecting data from tracepoint hits in the trace frame buffer. Supports the 'qRelocInsn' reply.

### Method
Packet (GDB remote serial protocol)

### Endpoint
QTStart

### Response
No explicit response format is documented.
```

--------------------------------

### -break-delete example with -break-list

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Breakpoint-Commands.html

Example showing how to delete breakpoint 1 and verify the breakpoint list is empty.

```gdb
(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)
```

--------------------------------

### -data-list-register-names example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Data-Manipulation.html

Example on a PPC MBX board showing -data-list-register-names with no arguments and with arguments 1 2 3.

```gdb
(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)
```

--------------------------------

### -catch-rethrow example with output

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/C_002b_002b-Exception-GDB_002fMI-Catchpoint-Commands.html

Example of using -catch-rethrow with a regexp, showing the catchpoint creation and the stop when the exception is rethrown.

```gdb
-catch-rethrow -r exception_type
^done,bkpt={number="1",type="catchpoint",disp="keep",enabled="y",
  what="exception rethrow",catch-type="rethrow",
  thread-groups=["i1"],
  regexp="exception_type",times="0"}
(gdb)
-exec-run
^running
(gdb)
~"\n"
~"Catchpoint 1 (exception rethrown), 0x00007ffff7ae00ed
  in __cxa_rethrow () from /lib64/libstdc++.so.6\n"
*stopped,bkptno="1",reason="breakpoint-hit",disp="keep",
  frame={addr="0x00007ffff7ae00ed",func="__cxa_rethrow",
  args=[],from="/lib64/libstdc++.so.6",arch="i386:x86-64"},
  thread-id="1",stopped-threads="all",core="6"
(gdb)
```

--------------------------------

### GDB trace command examples

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Create-and-Delete-Tracepoints.html

Examples of using the `trace` command with various location specifications: source file and line number, relative line offset, function name, exact start address of function, and an absolute address.

```gdb
(gdb) trace foo.c:121    // a source file and line number

(gdb) trace +2           // 2 lines forward

(gdb) trace my_function  // first source line of function

(gdb) trace *my_function // EXACT start address of function

(gdb) trace *0x2117c4    // an address
```

--------------------------------

### -exec-return example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Execution.html

Example GDB/MI session showing the -exec-return command after setting a breakpoint and running, displaying the new current frame.

```gdb
(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",disp="keep",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",
arch="i386:x86_64"}
(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",
arch="i386:x86_64"}
(gdb)
```

--------------------------------

### GDB x command example with instruction disassembly

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Memory.html

Shows the output of the x command with the i format and a count of 5, starting at $pc-6. The current instruction is marked with '=>'. This example illustrates how GDB displays memory contents and the current program counter marker.

```gdb
(gdb) x/5i $pc-6
   0x804837f <main+11>: mov    %esp,%ebp
   0x8048381 <main+13>: push   %ecx
   0x8048382 <main+14>: sub    $0x4,%esp
=> 0x8048385 <main+17>: movl   $0x8048460,(%esp)
   0x804838c <main+24>: call   0x80482d4 <puts@plt>
```

--------------------------------

### -enable-timings example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example showing enabling timings, running -break-insert main with timing output, disabling timings, and running -exec-run without timing.

```gdb
(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",thread-groups=["i1"],
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",disp="keep",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",arch="i386:x86_64"}
(gdb)
```

--------------------------------

### -info-gdb-mi-command example for unsupported command

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Support-Commands.html

Example showing the result when the command does not exist: the 'exists' field is "false".

```gdb
-info-gdb-mi-command unsupported-command
^done,command={exists="false"}
```

--------------------------------

### Example: -data-read-memory-bytes &a 10

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Data-Manipulation.html

Reads ten bytes of memory starting at address &a. The output shows the memory block with begin, offset, end, and contents fields.

```gdb
(gdb)
-data-read-memory-bytes &a 10
^done,memory=[{begin="0xbffff154",offset="0x00000000",
              end="0xbffff15e",
              contents="01000000020000000300"}]
(gdb)
```

--------------------------------

### -symbol-info-modules example output

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Symbol-Query.html

Example output from the -symbol-info-modules command, showing a list of Fortran modules grouped by source file.

```gdb
(gdb)
-symbol-info-modules
^done,symbols=
  {debug=
    [{filename="/project/gdb/testsuite/gdb.mi/mi-fortran-modules-2.f90",
      fullname="/project/gdb/testsuite/gdb.mi/mi-fortran-modules-2.f90",
      symbols=[{line="16",name="mod1"},
               {line="22",name="mod2"}]},
     {filename="/project/gdb/testsuite/gdb.mi/mi-fortran-modules.f90",
      fullname="/project/gdb/testsuite/gdb.mi/mi-fortran-modules.f90",
      symbols=[{line="16",name="mod3"},
               {line="22",name="modmany"},
               {line="26",name="moduse"}]}]}
```

--------------------------------

### Disassemble 3 instructions from start of main

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Data-Manipulation.html

Example of disassembling a limited number of instructions using the -n option. The output shows exactly 3 instructions.

```gdb
(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)
```

--------------------------------

### Example: Greet convenience function

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Functions-In-Python.html

A complete example of implementing a trivial convenience function that greets a user by name. The class is instantiated to register the function with GDB.

```APIDOC
## Example: Greet convenience function

### Description
Demonstrates how to implement a convenience function that returns a greeting string.

### Code
```python
class Greet (gdb.Function):
  """Return string to greet someone.
Takes a name as argument."""

  def __init__ (self):
    super (Greet, self).__init__ ("greet")

  def invoke (self, name):
    return "Hello, %s!" % name.string ()

Greet ()
```

### Usage
After loading the code into GDB, the function can be used in expressions:
```
(gdb) print $greet("Bob")
$1 = "Hello, Bob!"
```

```

--------------------------------

### C: Allocate array with malloc

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Arrays.html

Example C code showing how to allocate an array of integers using malloc. This is the setup for using the '@' operator to print the array.

```c
int *array = (int *) malloc (len * sizeof (int));
```

--------------------------------

### python multi-line command

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Python-Commands.html

Starts a multi-line Python script terminated by a line containing 'end'. Example: (gdb) python, then >print(23), then >end prints 23.

```gdb
(gdb) python
>print(23)
>end
23
```

--------------------------------

### -symbol-info-functions example (no options)

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Symbol-Query.html

Example GDB/MI session showing the output of -symbol-info-functions without options, listing all global functions grouped by source file.

```gdb
(gdb)
-symbol-info-functions
^done,symbols=
  {debug=
    [{filename="/project/gdb/testsuite/gdb.mi/mi-sym-info-1.c",
      fullname="/project/gdb/testsuite/gdb.mi/mi-sym-info-1.c",
      symbols=[{line="36", name="f4", type="void (int *)",
                description="void f4(int *);"},
               {line="42", name="main", type="int ()",
                description="int main();"},
               {line="30", name="f1", type="my_int_t (int, int)",
                description="static my_int_t f1(int, int);"}]},
     {filename="/project/gdb/testsuite/gdb.mi/mi-sym-info-2.c",
      fullname="/project/gdb/testsuite/gdb.mi/mi-sym-info-2.c",
      symbols=[{line="33", name="f2", type="float (another_float_t)",
                description="float f2(another_float_t);"},
               {line="39", name="f3", type="int (another_int_t)",
                description="int f3(another_int_t);"},
               {line="27", name="f1", type="another_float_t (int)",
                description="static another_float_t f1(int);"}]}]}
```

--------------------------------

### Create a style with gdb.StyleParameterSet

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Parameters-In-Python.html

Example showing how to create a new style 'my-style' using gdb.StyleParameterSet, and the resulting GDB output for 'show style my-style'.

```gdb
(gdb) python s = gdb.StyleParameterSet("my-style")
(gdb) show style my-style
style my-style background:  The "my-style" style background color is: none
style my-style foreground:  The "my-style" style foreground color is: none
style my-style intensity:  The "my-style" style display intensity is: normal
(gdb)
```

--------------------------------

### Compile and invoke GDB on charset-test

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Character-Sets.html

Commands to compile the example program with GCC and start GDB in non-windowed mode. The output shows the GDB version banner and prompt.

```shell
$ gcc -g charset-test.c -o charset-test
$ gdb -nw charset-test
GNU gdb 2001-12-19-cvs
Copyright 2001 Free Software Foundation, Inc.
…
(gdb)

```

--------------------------------

### -exec-next-instruction example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Execution.html

Example GDB/MI session showing the -exec-next-instruction command and its output, stopping at address 0x000100d4 on line 5 of hello.c.

```gdb
(gdb)
-exec-next-instruction
^running

(gdb)
*stopped,reason="end-stepping-range",
addr="0x000100d4",line="5",file="hello.c"
(gdb)
```

--------------------------------

### GDB target remote TCP example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/gdbserver-man.html

GDB command to connect to gdbserver via TCP to port 2345 on host 'the-target'. gdbserver must be started first to avoid 'Connection refused'.

```gdb
(gdb) target remote the-target:2345
```

--------------------------------

### -stack-info-frame command

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Stack-Manipulation.html

Gets info on the selected frame. Corresponds to GDB command 'info frame' or 'frame' (without arguments). Example shows output with frame level, address, function, file, line, and architecture.

```gdb
(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",
arch="i386:x86_64"}
(gdb)
```

--------------------------------

### Get type name of unsigned char type in GDB Guile

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Architectures-In-Guile.html

Example command that uses `arch-uchar-type` and `current-arch` to retrieve the type name of the unsigned char type for the current architecture. The output is "unsigned char".

```gdb
(gdb) guile (type-name (arch-uchar-type (current-arch)))
"unsigned char"
```

--------------------------------

### foo.c main calling foo for /m vs /s example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Machine-Code.html

Source file that includes foo.h and calls foo in main, used to demonstrate the difference between /m and /s disassembly output.

```c
#include "foo.h"
volatile int x, y;
int
main ()
{
  x = foo (y);
  return 0;
}

```

--------------------------------

### -target-disconnect example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Target-Manipulation.html

Example of disconnecting from the remote target, producing no output.

```gdb
(gdb)
-target-disconnect
^done
(gdb)
```

--------------------------------

### GDB command line with -ex and -x options

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/File-Options.html

Shows how to use -ex and -x options together to execute commands before running a program. The example runs 'target sim', 'load', sources a file 'setbreakpoints', and then runs 'run' on 'a.out'.

```shell
gdb -ex 'target sim' -ex 'load' \
   -x setbreakpoints -ex 'run' a.out
```

--------------------------------

### -target-detach example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Target-Manipulation.html

Example of detaching from the remote target, producing no output.

```gdb
(gdb)
-target-detach
^done
(gdb)
```

--------------------------------

### -target-file-delete example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-File-Transfer-Commands.html

Example of using -target-file-delete to delete a remote file.

```gdb
(gdb)
-target-file-delete remotefile
^done
(gdb)
```

--------------------------------

### List lines around class method

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Method-Names-in-Commands.html

Example of listing ten program lines around the 'initialize' class method using the 'list' command.

```gdb
list +[NSText initialize]
```

--------------------------------

### -exec-arguments example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Program-Context.html

Example of using -exec-arguments to set arguments '-v word'.

```gdb
(gdb)
-exec-arguments -v word
^done
(gdb)
```

--------------------------------

### maint info program-spaces output with vfork example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Inferiors-Connections-and-Programs.html

Example output showing multiple inferiors bound to the same program space, as a result of a vfork call.

```gdb
(gdb) maint info program-spaces
  Id   Executable
* 1    vfork-test
        Bound inferiors: ID 2 (process 18050), ID 1 (process 18045)
```

--------------------------------

### -file-list-exec-source-file example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-File-Commands.html

Example of the -file-list-exec-source-file command. Shows the command with a token 123 and its response including line, file, fullname, and macro-info fields.

```gdb
(gdb)
123-file-list-exec-source-file
123^done,line="1",file="foo.c",fullname="/home/bar/foo.c,macro-info="1"
(gdb)
```

--------------------------------

### -inferior-tty-set example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Miscellaneous-Commands.html

Example of setting the inferior TTY to /dev/pts/1, showing ^done.

```gdb
(gdb)
-inferior-tty-set /dev/pts/1
^done
(gdb)
```

--------------------------------

### Starting GDB on m4

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Sample-Session.html

Launches GDB on the m4 executable, showing the startup banner and the initial prompt.

```gdb
$ gdb m4
GDB is free software and you are welcome to 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.

GDB 19.0.50.20261019-git, Copyright 1999 Free Software Foundation, Inc...
(gdb)
```

--------------------------------

### GDB complete i example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Help.html

Lists possible completions for the beginning of a command 'i', showing 'if', 'ignore', 'info', and 'inspect'.

```gdb
complete i
```

```gdb
if
ignore
info
inspect
```

--------------------------------

### Use the builtin CPU simulator

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Target-Commands.html

Starts the builtin CPU simulator and loads the program. Note that specific memory maps, device drivers, or basic I/O may not be available.

```gdb
        target sim
        load
        run
```

--------------------------------

### string->argv example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Commands-In-Guile.html

Shows how to convert a string with spaces and quotes into a list of strings according to GDB's argv parsing rules. The output is shown as a Guile REPL result.

```scheme
scheme@(guile-user)> (string->argv "1 2\\ \"3 '4 \"5' \"6 '7\"")
$1 = ("1" "2 \"3" "4 \"5" "6 '7")
```

--------------------------------

### Display GDB help

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Invoking-GDB.html

Display all available options and briefly describe their use. 'gdb -h' is a shorter equivalent.

```shell
gdb -help
```

--------------------------------

### Compatible architecture example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Target-Description-Format.html

Example showing how to describe a target that can run binaries in the spu architecture in addition to the main powerpc:common architecture, as on the Cell Broadband Engine.

```xml
  <architecture>powerpc:common</architecture>
  <compatible>spu</compatible>
```

--------------------------------

### Run GDB with --args and shell expansion

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Mode-Options.html

Shows how the shell expands wildcards before GDB starts, so the inferior sees the expanded list. Use when you want the shell to expand arguments at GDB startup.

```shell
$ gdb --args ls *.c
```

--------------------------------

### -target-file-put example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-File-Transfer-Commands.html

Example of using -target-file-put to copy a local file to a remote target.

```gdb
(gdb)
-target-file-put localfile remotefile
^done
(gdb)
```

--------------------------------

### Example: Using Memory Ports with Bytevectors

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Memory-Ports-in-Guile.html

Example demonstrating how to use memory ports with Guile's bytevectors to fill a buffer of 10 integers in target memory.

```APIDOC
## Example: Using Memory Ports with Bytevectors

### Description
This example shows how to use a memory port to write a buffer of 10 integers to target memory.

### Code
```scheme
;; In the program: int buffer[10];
(use-modules (rnrs bytevectors))
(use-modules (rnrs io ports))
(define addr (parse-and-eval "buffer"))
(define n 10)
(define byte-size (* n 4))
(define mem-port (open-memory #:mode "r+" #:start
                              (value->integer addr) #:size byte-size))
(define byte-vec (make-bytevector byte-size))
(do ((i 0 (+ i 1)))
    ((>= i n))
    (bytevector-s32-native-set! byte-vec (* i 4) (* i 42)))
(put-bytevector mem-port byte-vec)
(close-port mem-port)
```
```

--------------------------------

### Example stop method implementation

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Breakpoints-In-Python.html

Example implementation of a stop method for a Breakpoint subclass.

```APIDOC
## Example stop method implementation

### Description
Example implementation of a `stop` method for a `gdb.Breakpoint` subclass. The method is called when the breakpoint is hit. It should return `True` to stop the inferior, or `False` to continue.

### Code
```python
class MyBreakpoint (gdb.Breakpoint):
      def stop (self):
        inf_val = gdb.parse_and_eval("foo")
        if inf_val == 3:
          return True
        return False
```
```

--------------------------------

### info connections output example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/Inferiors-Connections-and-Programs.html

Shows the output of the 'info connections' command, listing open target connections with their numbers, protocols, and descriptions. The asterisk indicates the connection of the current inferior.

```gdb
(gdb) info connections
  Num  What                        Description
* 1    extended-remote host:10000  Extended remote serial target in gdb-specific protocol
  2    native                      Native process
  3    core                        Local core dump file
```

--------------------------------

### substitute_prompt example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/gdb_002eprompt.html

Example call to substitute_prompt with escape sequences for frame and arguments, and the resulting string.

```python
substitute_prompt ("frame: \f, args: \p{print frame-arguments}")
```

```text
"frame: main, args: scalars"
```

--------------------------------

### -var-info-type example output

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Variable-Objects.html

Example output format for -var-info-type, showing the returned type string.

```gdb
 type=typename
```

--------------------------------

### -target-attach example

Source: https://sourceware.org/gdb/current/onlinedocs/gdb.html/GDB_002fMI-Target-Manipulation.html

Example of attaching to process 34, showing the resulting thread-created and stopped records.

```gdb
(gdb)
-target-attach 34
=thread-created,id="1"
*stopped,thread-id="1",frame={addr="0xb7f7e410",func="bar",args=[]}
^done
(gdb)
```
Tokens:
Raw