I have a process that runs as a daemon forking off child processes when requests come in. To control zombies I have the standard 
# Install signal handler for child processes
$SIG{'CHLD'} = sub { while (waitpid(-1,WNOHANG) > 0) {} };

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However, the child processes then have to make a system call and I need to trap the exit code eg.. 
my $res = system $cmd, $arg;

unless ($res == 0) {
    ...
}

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$? now contains -1 and $! 'No child processes', I understand that this is because of my $SIG{'CHLD'} handler. But how can I get the true exit code and message? I've tried 'local $SIG{'CHLD'} = '' prior to the sys call and that seems to work but looks very clumsy.

What is the best way to get at the exit code?

In reply to No child processes by Jonathan

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