d="RETURN-VALUES">RETURN VALUES</h1>

<p>EVP_MAC_fetch() returns a pointer to a newly fetched <b>EVP_MAC</b>, or NULL if allocation failed.</p>

<p>EVP_MAC_up_ref() returns 1 on success, 0 on error.</p>

<p>EVP_MAC_names_do_all() returns 1 if the callback was called for all names. A return value of 0 means that the callback was not called for any names.</p>

<p>EVP_MAC_free() returns nothing at all.</p>

<p>EVP_MAC_is_a() returns 1 if the given method can be identified with the given name, otherwise 0.</p>
