#!/usr/bin/perl -w
use File::Basename;
my ($daemon, @args) = @ARGV;

my $pid;
if($pid =fork()) {
  # i am parent..
  my $dname = basename($daemon);
  # maybe here you prefer
  # my $dname = basename($args[1]) . '.pid'; 
  open PIDFILE, ">/var/run/$dname" || die "cannot write pid file";
  print PIDFILE $pid;
  close PIDFILE;
}
else {
  exec($daemon, @args) || die "cannot execute $daemon: $!";
}