@deftypefun {gnutls_hmac_hd_t} {gnutls_hmac_copy} (gnutls_hmac_hd_t @var{handle})
@var{handle}: is a @code{gnutls_hmac_hd_t}  type

This function will create a copy of MAC context, containing all its current
state. Copying contexts for MACs registered using
@code{gnutls_crypto_register_mac()}  is not supported and will always result in an
error.

@strong{Returns:} new MAC context or NULL in case of an error.

@strong{Since:} 3.6.9
@end deftypefun