PHP Manual: Gets an exportable representation of a key into a string

Description

bool openssl_pkey_export ( mixed $key , string &$out [, string $passphrase [, array $configargs ]] )

openssl_pkey_export exports key as a PEM encoded string and stores it into out (which is passed by reference).

Note: You need to have a valid openssl.cnf installed for this function to operate correctly. See the notes under the installation section for more information.

Parameters

key
out
passphrase: The key is optionally protected by passphrase.
configargs: configargs can be used to fine-tune the export process by specifying and/or overriding options for the openssl configuration file. See openssl_csr_new for more information about configargs.

Return Values

Returns TRUE on success or FALSE on failure.