Actually, when you pass a callback, method doesn't return immediately, but waits for results and calls callback function.
(PECL memcached >= 0.1.0)
Memcached::getDelayed — Request multiple items
Memcached::getDelayed() issues a request to memcache for
multiple items the keys of which are specified in the
keys array. The method does not wait for response
and returns right away. When you are ready to collect the items, call
either Memcached::fetch() or
Memcached::fetchAll(). If with_cas
is true, the CAS token values will also be requested.
Instead of fetching the results explicitly, you can specify a result callback via
value_cb parameter.
keysArray of keys to request.
with_casWhether to request CAS token values also.
value_cb
The result callback or null.
Returns true on success or false on failure.
Use Memcached::getResultCode() if necessary.
Example #1 Memcached::getDelayed() example
<?php
$m = new Memcached();
$m->addServer('localhost', 11211);
$m->set('int', 99);
$m->set('string', 'a simple string');
$m->set('array', array(11, 12));
$m->getDelayed(array('int', 'array'), true);
var_dump($m->fetchAll());
?>The above example will output:
array(2) {
[0]=>
array(3) {
["key"]=>
string(3) "int"
["value"]=>
int(99)
["cas"]=>
float(2363)
}
[1]=>
array(3) {
["key"]=>
string(5) "array"
["value"]=>
array(2) {
[0]=>
int(11)
[1]=>
int(12)
}
["cas"]=>
float(2365)
}
}
Actually, when you pass a callback, method doesn't return immediately, but waits for results and calls callback function.