apache_setenv()
can be paired up with
apache_getenv()
across separate pages or for setting variables to pass to Server Side Includes (.shtml) that have been included in PHP scripts.
See Also
apache_getenv() - Get an Apache subprocess_env variable
PHP / apcu_clear_cache — DevDocs
apcu_clear_cache
(PECL apcu >= 4.0.0)
apcu_clear_cache
—
Clears the APCu cache
Description
apcu_clear_cache():bool
Clears the cache.
Parameters
This function has no parameters.
Return Values
Returns
true
always
See Also
apcu_cache_info() - Retrieves cached information from APCu's data store
Optionally pass the success or fail boolean value to this referenced variable.
ttl
TTL to use if the operation inserts a new value (rather than decrementing an existing one).
Return Values
Returns the current value of
key
's value on success, or
false
on failure
Examples
Example #1
apcu_dec()
example
<?phpecho"Let's do something with success",PHP_EOL;apcu_store('anumber',42);echoapcu_fetch('anumber'),PHP_EOL;echoapcu_dec('anumber'),PHP_EOL;echoapcu_dec('anumber',10),PHP_EOL;echoapcu_dec('anumber',10,$success),PHP_EOL;var_dump($success);echo"Now, let's fail",PHP_EOL,PHP_EOL;apcu_store('astring','foo');$ret=apcu_dec('astring',1,$fail);var_dump($ret);var_dump($fail);?>
The above example will output something similar to:
Let's do something with success
42
41
31
21
bool(true)
Now, let's fail
bool(false)
bool(false)
Atomically attempts to find
key
in the cache, if it cannot be found
generator
is called, passing
key
as the only argument. The return value of the call is then cached with the optionally specified
ttl
, and returned.
Note
:
When control enters
apcu_entry()
the lock for the cache is acquired exclusively, it is released when control leaves
apcu_entry()
: In effect, this turns the body of
generator
into a critical section, disallowing two processes from executing the same code paths concurrently. In addition, it prohibits the concurrent execution of any other APCu functions, since they will acquire the same lock.
Warning
The only APCu function that can be called safely by
generator
is
apcu_entry()
.
Parameters
key
Identity of cache entry
generator
A callable that accepts
key
as the only argument and returns the value to cache.
ttl
Time To Live; store
var
in the cache for
ttl
seconds. After the
ttl
has passed, the stored variable will be expunged from the cache (on the next request). If no
ttl
is supplied (or if the
ttl
is
0
), the value will persist until it is removed from the cache manually, or otherwise fails to exist in the cache (clear, restart, etc.).
A
string
, or an
array
of strings, that contain keys.
Return Values
Returns
true
if the key exists, otherwise
false
Or if an
array
was passed to
keys
, then an array is returned that contains all existing keys, or an empty array if none exist.
Examples
Example #1
apcu_exists()
example
<?php$fruit='apple';$veggie='carrot';apcu_store('foo',$fruit);apcu_store('bar',$veggie);if(apcu_exists('foo')){echo"Foo exists: ";echoapcu_fetch('foo');}else{echo"Foo does not exist";}echoPHP_EOL;if(apcu_exists('baz')){echo"Baz exists.";}else{echo"Baz does not exist";}echoPHP_EOL;$ret=apcu_exists(array('foo','donotexist','bar'));var_dump($ret);?>
The above example will output something similar to:
Foo exists: apple
Baz does not exist
array(2) {
["foo"]=>
bool(true)
["bar"]=>
bool(true)
}
See Also
apcu_cache_info() - Retrieves cached information from APCu's data store
apcu_fetch() - Fetch a stored variable from the cache