perl, daemon

sub become_daemon {
    my $child = fork;
    die "Can't fork: $!" unless      defined($child);
    exit(0) if $child; # parent dies;
    POSIX::setsid(); # become session leader
    open(STDIN,"</dev/null");
    open(STDOUT,">/dev/null");
    open(STDERR, '>&STDOUT');
    umask(0); # forget file mode creation mask
    $ENV{PATH} = '/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin';
    delete @ENV{'IFS', 'CDPATH', 'ENV', 'BASH_ENV'};
}
become_daemon();