(PECL uopz >= 1.0.3)
uopz_backup — Backup a function
$class
   , string $function
   )$function
   )Backup a function at runtime, to be restored on shutdown
classThe name of the class containing the function to backup
functionThe name of the function
Example #1 uopz_backup() example
<?php
uopz_backup("fgets");
uopz_function("fgets", function(){
    return true;
});
var_dump(fgets());
?>
The above example will output something similar to:
bool(true)