I am trying to catch the exit code of a shell script executed by my script. I used a friends code to 'daemonize' and then mask for signals with the 'POSIX' module.

The problem that I now have is once the following piece of code is run '$?' is always '-1' regardless of the exit from the last command run in (``)'s.

I have read that once a new sigchld is installed the $? cannot be trusted.

My question, is there any way to retain the '$?' or like behavior after messing with sigchld? 



# START_SUB
sub setSigDisposition() {
  my ($sighandler,$snum);

  #
  # The set of signals to mask
  #
  my $sigset = POSIX::SigSet->new;
  $sigset->fillset();

  #
  # Don't mask these signals because wouldn't want to continue
  # if one these sent, even in critical section(s).
  #
  $sigset->delset( &POSIX::SIGILL );
  $sigset->delset( &POSIX::SIGSEGV );
  $sigset->delset( &POSIX::SIGFPE );
  $sigset->delset( &POSIX::SIGINT );

  foreach $snum( split(' ', $Config{sig_num}) ){
    $SIG{CHLD} = 'IGNORE';
    if( $snum == &POSIX::SIGILL || $snum == &POSIX::SIGSEGV || $snum =
+= &POSIX::SIGFPE || $snum == &POSIX::SIGINT ){
      $sighandler = "main::death";
    }
#    elsif( $snum == &POSIX::SIGTERM ){
#      $sighandler = "main::shutdown";
#    }
    else{
      $sighandler = "main::reaper";
    }

    # Set signal disposition ...
    POSIX::sigaction(
      $snum,
      POSIX::SigAction->new( $sighandler,
      POSIX::SigSet->new,
      &POSIX::SA_NOCLDSTOP ),
      POSIX::SigAction->new( $sighandler,
      POSIX::SigSet->new,
      &POSIX::SA_NOCLDSTOP )
    );
  }
  return $sigset;
}
# END_SUB

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Thanks! -Bryan

In reply to sigchild and $? by Chapter_01

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