<?php
  $pid = pcntl_fork();
  if ($pid == -1) {
     die("could not fork"); 
  } else if ($pid) {
     exit(); // we are the parent 
  } else {
     // we are the child
  }

// detatch from the controlling terminal
  if (!posix_setsid()) {
    die("could not detach from terminal");
  }

// setup signal handlers
  pcntl_signal(SIGTERM, "sig_handler");
  pcntl_signal(SIGHUP, "sig_handler");

// loop forever performing tasks
  while(1) {
    // do something interesting here
}

function sig_handler($signo) {
     switch($signo) {
         case SIGTERM:
             // handle shutdown tasks
             exit;
             break;
         case SIGHUP:
             // handle restart tasks
             break;
         default:
             // handle all other signals
     }
}
?<