Debugging with GDB

Node:Mode Options, Previous:File Options, Up:Invoking GDB

#### Choosing modes

You can run GDB in various alternative modes--for example, in batch mode or quiet mode.

`-nx`
`-n`
  Do not execute commands found in any initialization files. Normally, GDB executes the commands in these files after all the command options and arguments have been processed. See Command files.
`-quiet`
`-silent`
`-q`
  "Quiet". Do not print the introductory and copyright messages. These messages are also suppressed in batch mode.
`-batch`
  Run in batch mode. Exit with status `0` after processing all the command files specified with `-x` (and all commands from initialization files, if not inhibited with `-n`). Exit with nonzero status if an error occurs in executing the GDB commands in the command files.

  Batch mode may be useful for running GDB as a filter, for example to download and run a program on another computer; in order to make this more useful, the message

                Program exited normally.

  (which is ordinarily issued whenever a program running under GDB control terminates) is not issued when running in batch mode.

`-nowindows`
`-nw`
  "No windows". If GDB comes with a graphical user interface (GUI) built in, then this option tells GDB to only use the command-line interface. If no GUI is available, this option has no effect.
`-windows`
`-w`
  If GDB includes a GUI, then this option requires it to be used if possible.
`-cd` directory``
  Run GDB using directory as its working directory, instead of the current directory.
`-fullname`
`-f`
  GNU Emacs sets this option when it runs GDB as a subprocess. It tells GDB to output the full file name and line number in a standard, recognizable fashion each time a stack frame is displayed (which includes each time your program stops). This recognizable format looks like two `\032` characters, followed by the file name, line number and character position separated by colons, and a newline. The Emacs-to-GDB interface program uses the two `\032` characters as a signal to display the source code for the frame.
`-epoch`
  The Epoch Emacs-GDB interface sets this option when it runs GDB as a subprocess. It tells GDB to modify its print routines so as to allow Epoch to display values of expressions in a separate window.
`-annotate` level``
  This option sets the annotation level inside GDB. Its effect is identical to using `set annotate` level`` (see Annotations). Annotation level controls how much information does GDB print together with its prompt, values of expressions, source lines, and other types of output. Level 0 is the normal, level 1 is for use when GDB is run as a subprocess of GNU Emacs, level 2 is the maximum annotation suitable for programs that control GDB.
`-async`
  Use the asynchronous event loop for the command-line interface. GDB processes all events, such as user keyboard input, via a special event loop. This allows GDB to accept and process user commands in parallel with the debugged process being run1, so you don't need to wait for control to return to GDB before you type the next command. (Note: as of version 5.1, the target side of the asynchronous operation is not yet in place, so `-async` does not work fully yet.)

  When the standard input is connected to a terminal device, GDB uses the asynchronous event loop by default, unless disabled by the `-noasync` option.

`-noasync`
  Disable the asynchronous event loop for the command-line interface.
`--args`
  Change interpretation of command line so that arguments following the executable file are passed as command line arguments to the inferior. This option stops option processing.
`-baud` bps``
`-b` bps``
  Set the line speed (baud rate or bits per second) of any serial interface used by GDB for remote debugging.
`-tty` device``
`-t` device``
  Run using device for your program's standard input and output.
`-tui`
  Activate the Terminal User Interface when starting. The Terminal User Interface manages several text windows on the terminal, showing source, assembly, registers and GDB command outputs (see GDB Text User Interface). Do not use this option if you run GDB from Emacs (see Using GDB under GNU Emacs).
`-interpreter` interp``
  Use the interpreter interp for interface with the controlling program or device. This option is meant to be set by programs which communicate with GDB using it as a back end.

  `--interpreter=mi` (or `--interpreter=mi1`) causes GDB to use the gdb/mi interface (see The GDB/MI Interface). The older GDB/MI interface, included in GDB version 5.0 can be selected with `--interpreter=mi0`.

`-write`
  Open the executable and core files for both reading and writing. This is equivalent to the `set write on` command inside GDB (see Patching).
`-statistics`
  This option causes GDB to print statistics about time and memory usage after it completes each command and returns to the prompt.
`-version`
  This option causes GDB to print its version number and no-warranty blurb, and exit.

#### Footnotes

1. GDB built with DJGPP tools for MS-DOS/MS-Windows supports this mode of operation, but the event loop is suspended when the debuggee runs.