You can always ask GDB itself for information on its commands, using the command help.
- help or h
- You can use help (h) with no arguments to
display a short list of named classes of commands:
(gdb) help List of classes of commands: running -- Running the program stack -- Examining the stack data -- Examining data breakpoints -- Making program stop at certain points files -- Specifying and examining files status -- Status inquiries support -- Support facilities user-defined -- User-defined commands aliases -- Aliases of other commands obscure -- Obscure features Type "help" followed by a class name for a list of commands in that class. Type "help" followed by command name for full documentation. Command name abbreviations are allowed if unambiguous. (gdb)
- help class
- Using one of the general help classes as an argument, you can get a
list of the individual commands in that class. For example, here's the
help display for the class status:
(gdb) help status Status inquiries. List of commands: show -- Generic command for showing things set with "set" info -- Generic command for printing status Type "help" followed by command name for full documentation. Command name abbreviations are allowed if unambiguous. (gdb)
- help command
- With a command name as help argument, GDB displays a short paragraph on how to use that command.
- complete args
- The complete
args command lists all the possible completions
for the beginning of a command. Use args to specify the beginning of the
command you want completed. For example:
info inspect ignore
This is intended for use by GNU Emacs.
In addition to help, you can use the GDB commands info and show to inquire about the state of your program, or the state of GDB itself. Each command supports many topics of inquiry; this manual introduces each of them in the appropriate context. The listings under info and show in the index point to all the sub-commands.
- This command (abbreviated i) is for describing the state of your program. For example, you can list the arguments given to your program with info args, list the registers currently in use with info registers, or list the breakpoints you've set with info breakpoints. You can get a complete list of the info sub-commands with help info.
- You can assign the result of an expression to an environment variable with set. For example, you can set the GDB prompt to a $-sign with set prompt $.
- In contrast to info, show is for describing
the state of GDB itself.
You can change most of the things you can show, by using the
related command set; for example, you can control what number
system is used for displays with set radix, or simply inquire
which is currently in use with show radix.
To display all the settable parameters and their current values, you can use show with no arguments; you may also use info set. Both commands produce the same display.
Here are three miscellaneous show subcommands, all of which are exceptional in lacking corresponding set commands:
- show version
- Show what version of GDB is running. You should include this information in GDB bug-reports. If multiple versions of GDB are in use at your site, you may occasionally want to determine which version of GDB you're running; as GDB evolves, new commands are introduced, and old ones may wither away. The version number is also announced when you start GDB.
- show copying
- Display information about permission for copying GDB.
- show warranty
- Display the GNU NO WARRANTY statement.