Tells whether the given file is a regular file.
Path to the file.
Returns true if the filename exists and is a regular file, false otherwise.
Because PHP's integer type is signed and many platforms use 32bit integers, some filesystem functions may return unexpected results for files which are larger than 2GB.
Exceptions and Errors
Upon failure, an E_WARNING is emitted.
The results of this function are cached. See clearstatcache for more details.
As of PHP 5.0.0, this function can also be used with some URL wrappers. Refer to to determine which wrappers support stat family of functionality.