Re: [PATCH] ptrace on stopped processes (2.4)

Werner Almesberger
2003-03-25T13:37:43Z

Daniel Jacobowitz wrote:
> No, that's not what I meant. When you attach using GDB, there is no
> way for GDB to determine if the process was previously stopped or
> running.

Likewise, there's a race condition with any other concurrent use
of SIGSTOP.

Perhaps one could introduce a PTRACE_ATTACH2 that uses "addr" to
indicate the signal that should be used to sychronize attaching.
That way, programs that use STOP/CONT for their own purposes could
be attached to with ptrace(PTRACE_ATTACH2,pid,SIGTRAP,0), or such.

If the process is already stopped, the debugger would be notified
with WSTOPSIG set to that signal instead of SIGTRAP.

- Werner

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/ Werner Almesberger, Buenos Aires, Argentina wa@almesberger.net /
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