php man page for apc_cas

APC_CAS(3)								 1								APC_CAS(3)

apc_cas - Updates an old value with a new value

SYNOPSIS
       bool apc_cas (string  $key, int	$old, int  $new)

DESCRIPTION
       apc_cas(3)  updates  an	already existing integer value if the $old parameter matches the currently stored value with the value of the $new
       parameter.

PARAMETERS
	      o $key
		- The key of the value being updated.

	      o $old
		- The old value (the value currently stored).

	      o $new
		- The new value to update to.

RETURN VALUES
	Returns TRUE on success or FALSE on failure.

EXAMPLES
       Example #1

	      apc_cas(3) example

	      <?php
	      apc_store('foobar', 2);
	      echo '$foobar = 2', PHP_EOL;
	      echo '$foobar == 1 ? 2 : 1 = ', (apc_cas('foobar', 1, 2) ? 'ok' : 'fail'), PHP_EOL;
	      echo '$foobar == 2 ? 1 : 2 = ', (apc_cas('foobar', 2, 1) ? 'ok' : 'fail'), PHP_EOL;

	      echo '$foobar = ', apc_fetch('foobar'), PHP_EOL;

	      echo '$f__bar == 1 ? 2 : 1 = ', (apc_cas('f__bar', 1, 2) ? 'ok' : 'fail'), PHP_EOL;

	      apc_store('perfection', 'xyz');
	      echo '$perfection == 2 ? 1 : 2 = ', (apc_cas('perfection', 2, 1) ? 'ok' : 'epic fail'), PHP_EOL;

	      echo '$foobar = ', apc_fetch('foobar'), PHP_EOL;
	      ?>

	      The above example will output something similar to:

	      $foobar = 2
	      $foobar == 1 ? 2 : 1 = fail
	      $foobar == 2 ? 1 : 2 = ok
	      $foobar = 1
	      $f__bar == 1 ? 2 : 1 = fail
	      $perfection == 2 ? 1 : 2 = epic fail
	      $foobar = 1

SEE ALSO 
apc_dec(3), apc_store(3).
PHP Documentation Group 														APC_CAS(3)