Deletes filename. Similar to the Unix C unlink() function. Returns TRUE on success or FALSE on failure.
Note: As of PHP 5.0.0 unlink() can also be used with some URL wrappers. Refer to Appendix M for a listing of which wrappers support unlink().
Note: Context support was added with PHP 5.0.0. For a description of contexts, refer to Reference CLIII, Stream Functions.
See also rmdir() for removing directories.