Re: [Monotone-devel] auto updates

[Nuno Lucas]

On 10/29/06, Zack Weinberg <address@hidden> wrote:
> On 10/29/06, Nathaniel Smith <address@hidden> wrote:
> >
> > It should be possible to deal with zombies through some POSIX hackery,
> > no?  The only tricky bit is that we _do_ sometimes want to wait for a
> > process, so we can't just unconditionally get rid of zombies...
>
> Fork a child, which forks a grandchild and exits.  Grandchild execs
> what you really wanted to run.  wait() returns for the child, and the
> grandchild gets reparented to init.

This seems a bit of a hack when a simple solution is easy.

Just do this for POSIX systems (I don't believe there is a problem
with zombie processes on other systems):

static void signal_handler( int sig, siginfo_t* si, void * context )
{
  int status;
  wait (&status);
}

main( ... )
{
   struct sigaction sigact;
   memset( &sigact, 0, sizeof(sigact) );
   sigact.sa_sigaction = &signal_handler;
   sigact.sa_flags     = SA_SIGINFO;
   sigaction( SIGCHLD, &sigact, NULL );
  ...
}


Regards,
~Nuno Lucas