(PHP 4 = 4.2.0)
Returns a positive key resource identifier on success, or FALSE on error.
openssl_get_publickey() extracts the public key from certificate and prepares it for use by other functions. certificate can be one of the following:
a string having the format file://path/to/file.pem. The named file must contain a PEM encoded certificate/private key (it may contain both).
A PEM formatted private key.