I typically use a variation of this 'daemonize' code taken from perlipc. This sets up the script's environment and disassociates it from the caller entirely.

sub daemonize {
   chdir '/'               or die "Can't chdir to /: $!";
   open STDIN, '/dev/null' or die "Can't read /dev/null: $!";
   open STDOUT, '>/dev/null'
                                       or die "Can't write to /dev/nul
+l: $!";
   defined(my $pid = fork) or die "Can't fork: $!";
   exit if $pid;
   setsid                  or die "Can't start a new session: $!";
   open STDERR, '>&STDOUT' or die "Can't dup stdout: $!";
}
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You could also open STDOUT to point to, say, a log file here. Or a tied filehandle passing its data to syslog.