Hello, I can not distinguish the died fork from alive: killing it with 0 signal always returns 1. 
$ perl -Mstrict -wE 'my $pid = fork; if( $pid ){ sleep 3; say kill 0 =
+> $pid; waitpid $pid => 0; } else { exit; }'
1
$

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Here I wait for 3 seconds, check if the process exists and it does. But waitpid returns immediately which means that process is dead.

UPD.I mean, check for process existence within several seconds as I have many of them for SIGTERM and, later, to SIGKILL those still exist.

Thank you.

In reply to Check if forked process is dead by petr999

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