Re^3: forking and timeouts

No it's the other way round. It will always be 0 in the child process, and the PID of the child process in the parent.

To show it a bit clearer perhaps:

$pid = fork();

if (!defined $pid) {
  print "Fork failed: $@";
} elsif ($pid) {
  print "I am the parent, my PID is $$ and my child's PID is $pid\n";
} else {
  print "I am the child, my PID is $$ and my parent's PID is " . getpp
+id() . "\n";
}
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Re^4: forking and timeouts by Earindil (Beadle) on Aug 09, 2007 at 16:10 UTC
So based on the comments and more reading. This is what I came up with. Make more sense? The bolded parts are ones that I'm not sure I even need. Bits and pieces of this were pulled from other scripts I came across. foreach my $node (@nodes) { print "$node "; chomp $node; wait_for_a_kid() if keys %pid_to_node > 8; $pid = fork; if ($pid) { ## parent does... $pid_to_node{$pid} = $node; } else { local $SIG {ALRM} = sub { kill -15, $$ or die "kill: $!"; print "\tKilled PID $$\n"}; # Just SIGTERM. eval { ## child does... setpgrp(0,0); print $$."\n"; exit !&GetSvrStatus($node); alarm 5; waitpid $pid => 0; }; } } ## final reap: 1 while wait_for_a_kid();	[reply]

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Re^4: forking and timeouts
by Earindil (Beadle) on Aug 09, 2007 at 16:10 UTC

foreach my $node (@nodes) {
        print "$node ";
        chomp $node;
        wait_for_a_kid() if keys %pid_to_node > 8;
        $pid = fork;
        if ($pid) {
                ## parent does...
                $pid_to_node{$pid} = $node;
        }
        else {
                local $SIG {ALRM} = sub {
                kill -15, $$ or die "kill: $!";
                print "\tKilled PID $$\n"}; # Just SIGTERM.
                eval {
                        ## child does...
                        setpgrp(0,0);
                        print $$."\n";
                        exit !&GetSvrStatus($node);
                        alarm 5;
                        waitpid $pid => 0;
                };
        }
}
## final reap:
1 while wait_for_a_kid();

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