NOTE:

•To use attach, your program must be running in an environment which supports processes; for example, attach does not work for programs on bare-board targets that lack an operating system.

•You must also have permission to send the process a signal.

•When you use attach, the debugger finds the program running in the process first by looking in the current working directory, then (if the program is not found) by using the source file search path (see “Specifying source directories” (page 79)). You can also use the file command to load the program. See “Commands to specify files” (page 125).

•GDB stops the process being attached for debugging. You can examine and modify an attached process with the GDB commands that are available when you start processes with run. You can insert breakpoints; you can step and continue; you can modify storage. See “Breakpoints” (page 51). If you want the process to continue running, you can use the continue command after attaching GDB to the process.

detach When you have finished debugging the attached process, you can use the detach command to release it from GDB control. The process continues its execution after being detached. After the detach command, that process and GDB become completely independent once more, and you are ready to attach another process or start one with run. detach does not repeat if you press RET again after executing the command.

If you exit GDB or use the run command while you have an attached process, you kill that process. By default, GDB asks for confirmation if you try to do either of these things; you can control whether or not you need to confirm by using the set confirm command (see “Optional warnings and messages” (page 284)).

NOTE: When GDB attaches to a running program you may get a message saying "Attaching to process #nnnnn failed."

The most likely cause for this message is that you have attached to a process that was started across an NFS mount. Versions of the HP-UX kernel before 11.x have a restriction that prevents a debugger from attaching to a process started from an NFS mount, unless the mount was made non-interruptible with the -nointrflag, see mount(1).

4.8 Killing the child process

Following command is used to kill the child process:

kill Kill the child process in which your program is running under GDB.

The kill command is useful if you wish to debug a core dump instead of a running process. GDB ignores any core dump file while your program is running.

4.8 Killing the child process

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