#!/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"; } }