Re: [PATCH] BZ #14782 system async cancellation

[Rich Felker <dalias at aerifal dot cx>]

On Thu, Nov 01, 2012 at 01:30:30PM +0100, Andreas Schwab wrote:
> Rich Felker <dalias@aerifal.cx> writes:
> 
> > On Thu, Nov 01, 2012 at 08:31:02AM +0100, Andreas Schwab wrote:
> >> Rich Felker <dalias@aerifal.cx> writes:
> >> 
> >> > -/* We have to and actually can handle cancelable system().  The big
> >> > -   problem: we have to kill the child process if necessary.  To do
> >> > -   this a cleanup handler has to be registered and is has to be able
> >> > -   to find the PID of the child.  The main problem is to reliable have
> >> > -   the PID when needed.  It is not necessary for the parent thread to
> >> > -   return.  It might still be in the kernel when the cancellation
> >> > -   request comes.  Therefore we have to use the clone() calls ability
> >> > -   to have the kernel write the PID into the user-level variable.  */
> >> > -#ifndef FORK
> >> > -# define FORK() \
> >> > -  INLINE_SYSCALL (clone, 3, CLONE_PARENT_SETTID | SIGCHLD, 0, &pid)
> >> > -#endif
> >> 
> >> What about the other uses?
> >
> > Please clarify. Did I miss something?
> 
> Yes, all the other uses of FORK.

Could you please clarify. FORK does not appear anywhere else in either
of these two files except the #ifdef in sysdeps/posix/system.c, where
it's intended that the code in the #else clause be used.

Rich