Have a look at Re: Perl Daemons and SIGHUP. Probably it solves your problem.

Regards
McA

Thanks - here's a link to the solution: http://www.perlmonks.org/?node_id=440924 although as I noted in the thread, the author seems to have sometimes written SIGINT where he meant to write SIGHUP. If you copy the code and make that correction in two places, it works correctly.

If you follow the link in the original post, it takes you to perlipc doc containing code that illustrates the problem.

Looks like it's known problem in perl.
Also, similar issue Can't catch signals after an exec?

Code can be simplified to


$sub = sub { exec "perl $0" };
$SIG{INT} = $sub;
$SIG{USR1} = $sub;

while(1) {
    print ++$counter, "\n";
    sleep 1;
}
[download]

(if you press Ctrl-C, it restarts only once)
Workaround for example in perldoc:

#!/usr/bin/env perl

    use POSIX ();
    use FindBin ();
    use File::Basename ();
    use File::Spec::Functions;
    $| = 1;
    # make the daemon cross-platform, so exec always calls the script
    # itself with the right path, no matter how the script was invoked
+.
    print STDERR "STARTED\n";
    my $script = File::Basename::basename($0);
    my $SELF = catfile($FindBin::Bin, $script);
    # POSIX unmasks the sigprocmask properly
    my $need_restart = 0;
    $SIG{HUP} = sub {
    print "got SIGHUP\n";
    $need_restart = 1;
    };
    code();
    sub code {
    print "PID: $$\n";
    print "ARGV: @ARGV\n";
    my $count = 0;
    while (++$count) {
    sleep 2;
    if ($need_restart) {
    exec($SELF, @ARGV) || die "$0: couldn't restart: $!";
    }
    print "$count\n";
    }
    }
[download]


(i.e. need to call exec() outside of signal handler)

And another workaround is posted above by McA Re: Using SIGHUP to restart a daemon