Dear Monks

After fork()'ing, I am unable to catch a CHLD signal in the parent. In my example, the child process does nothing and calls die(). The parent would like to know that the CHLD process has terminated.

use strict;
use warnings;
use 5.010;

my $pid = fork;

if (!defined $pid) {
    die "Couldn't fork: $!";
}

if ($pid) {  #then in parent

    local $SIG{CHLD} = sub {say 'caught it';};
    say 'hello world';
}
else { #then in child

   die; 
}

--output:--
hello world

[download]

My expected output:

caught it
hello world

#or

hello world
caught it

[download]

In reply to why can't I catch CHLD signal? by 7stud

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