#!/usr/bin/perl

use POSIX;

BEGIN{($cmd, $out, $mail, $append)=@ARGV}

my $child=fork;

die $! unless defined $child;

exit 0 if $child;

setsid;

close STDIN; #, q(<), q(/dev/null);

open STDERR, q(>&), STDERR;

open STDOUT, q(|-), qq(tee @{[$append && q(-a )]}$out|tail|mail -s $out $mail);

exec $cmd;