I've got a program which is irritating me because of unreliable signals. If you run the program below then you'll probably see that it never finishes because some of the SIGCHLD signals have go missing due to the signal handler being engaged when they are issued. I think that POSIX and sigation is the way to go. In the spirit of Laziness (one of the great perl virtues ;-) - has anyone done this before? (I've been running this under Linux 2.2.16 and perl 5.6.0) 
use strict;
$|=1;

my $forked = 0;
$SIG{CHLD} = \&REAPER;          # set handler for fork

for (1..10)
{
    my $pid = fork();
    die "Fork failed" unless defined $pid;
    if ($pid == 0)
    {
        print "Hello $$\n";
        sleep 1;
        print "Bye $$\n";
        exit;
    }
    else
    {
        $forked++;
        print "Started child $pid\n";
    }
}

print "Waiting for children to finish..";
while ($forked > 0)
{
    print "[$forked] ";
    sleep 1;
}
print "Done\n";

exit;

sub REAPER
{
    my $pid = wait;
    $SIG{CHLD} = \&REAPER;      # reinstall for sysV (not needed)
    print "Finished child process $pid" . ($? ? " with exit $?" : "") 
+. "\n";
    $forked--;
}

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In reply to POSIX and sigaction by ncw

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