cheat sheets.

<?php 
$SEMKey = "123456" ; 

## Get Semaphore id 
$seg = sem_get( $SEMKey, 2, 0666, -1) ; 

if ( $argv[1]=="remove" ) { 
    sem_remove($seg); 
} 

echo "Try to acquire ..." 
sem_acquire($seg); 
echo "Acquired...\n" ; 

echo "Press Any Key to continue...\n"; 
$fh = fopen("php://stdin", "r"); 
$a = fgets( $fh); 
fclose($fh); 

sem_release($seg); 
?>