No external libraries are needed to build this extension.
There is no installation needed to use these functions; they are part of the PHP core.
The behaviour of these functions is affected by settings in php.ini.
Table 1. Variables Configuration Options
For further details and definition of the PHP_INI_* constants see ini_set()
Here is a short explanation of the configuration directives.
The unserialize callback function will called (with the undefind class' name as parameter), if the unserializer finds an undefined class which should be instanciated. A warning appears if the specified function is not defined, or if the function doesn't include/implement the missing class. So only set this entry, if you really want to implement such a callback-function.
See also unserialize().
This extension has no resource types defined.
This extension has no constants defined.