Re: gdb 6.3 misses breakpoint on Linux when inferior does clone()

Daniel Jacobowitz
2005-06-01T13:23:41Z

On Tue, May 31, 2005 at 10:05:22AM -0700, tronics93-gdb@yahoo.com wrote:
> >> The kernel does not provide any interface for GDB to know whether
> or
> >> not a clone syscall has used CLONE_VM.
> >>
> >> [Satish] Doesn't ptrace(PTRACE_GETREGS,...) provide that
> information >>? Or is that arch. specific ?
>
> >No, it does not.
>
> The following code snippet gets the flags passed in to clone() (on
> x86):
>
> unsigned long regs[FRAME_SIZE];
>
> if (ptrace(PTRACE_GETREGS, pid, 0, &regs) < 0)
> perror("ptrace_getregs failed:");
>
> printf("syscall=%d, arg1=%#x, arg2=%#x\n", regs[ORIG_EAX],
> regs[EBX], regs[ECX]);

Only if you're stopped at the clone. Hmm. Good point; perhaps we can
recover them from registers when we receive the clone event.

It could probably be implemented if someone spent the time.