官方手册中已经给你详细的说明
例如
--TEST--
APC: apc_store/fetch with strings
--SKIPIF--
<?php require_once(dirname(__FILE__) . '/skipif.inc'); ?>
--INI--
apc.enabled=1
apc.enable_cli=1
apc.file_update_protection=0
--FILE--
<?php
$foo = 'hello world';
var_dump($foo);
apc_store('foo',$foo);
$bar = apc_fetch('foo');
var_dump($bar);
$bar = 'nice';
var_dump($bar);
apc_store('foo\x00bar', $foo);
$bar = apc_fetch('foo\x00bar');
var_dump($bar);
?>
===DONE===
<?php exit(0); ?>
--EXPECTF--
string(11) "hello world"
string(11) "hello world"
string(4) "nice"
string(11) "hello world"
===DONE===
apc_store
bool apc_store ( string $key , mixed $var [, int $ttl = 0 ] )
apc_add
bool apc_add ( string $key , mixed $var [, int $ttl = 0 ] )
apc_fetch
mixed apc_fetch ( mixed $key [, bool &$success ] )
apc_delete
mixed apc_delete ( string $key )
apc_clear_cache
bool apc_clear_cache ([ string $cache_type ] )
apc_exists
mixed apc_exists ( mixed $keys )
程序逻辑就是上述函数的排列组合