301058@LOU-PC0288 /Work/METABASE
$ perl forktest.pl
nofork: ALARM!

nofork: done...


301058@LOU-PC0288 /Work/METABASE
$ perl forktest.pl a
PID(2560): ALARM!

PID(0): QUITTING!

PID(2560): done...


301058@LOU-PC0288 /Work/METABASE
$ cat forktest.pl
use strict;
use warnings;

my $prefix="nofork";
my $PID;

$SIG{INT} = sub { die "$prefix: QUITTING!\n\n"; };
$SIG{ALRM} = sub { print "$prefix: ALARM!\n\n"; kill 2,$PID if $PID; };

alarm(5);

if (@ARGV) {
        # with any argument we fork, o/w we don't
        $PID = fork;
        $prefix = "PID($PID)";
}

# Wait long enough for alarm to trigger
my $t = time;
while ($t + 10 > time) {
        # doze
}
print "$prefix: done...\n\n";
alarm(0);

301058@LOU-PC0288 /Work/METABASE
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