Hi, I'm trying to read the STDOUT and STDERR of a program using this code: 
defined( my $pid = open( FROM_CHILD, "-|" ) ) or die "can't fork: $!";
if ($pid) {
    my @output = <FROM_CHILD>;
    close FROM_CHILD;
} else {
    open STDERR, ">&STDOUT" or die "Can't dup STDOUT";
    exec @command or die "can't exec: $!";
}

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Problem is: sometimes, with a particular @command, the parent just idles while the child has become a zombie. I want to know if the above is safe from zombies, ie. it will *never* under any circumstance idle while the child is a zombie. The documentation of close says:
Closing a pipe also waits for the process executing on the pipe to complete, in case you want to look at the output of the pipe afterwards, and implicitly puts the exit status value of that command into $?.
It seems to me that the close should reap the zombie. So I guess the parent is idling while reading the child's output. How can it not idle? Why does it idle? Thanks!

In reply to Protection from zombies by nomis80

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