in a case insensitive way.

     *Returns:* an id of the specified in a string compression method,
     or ‘GNUTLS_COMP_UNKNOWN’ on error.

gnutls_compression_get_name
---------------------------

 -- Function: const char * gnutls_compression_get_name
          (gnutls_compression_method_t ALGORITHM)
     ALGORITHM: is a Compression algorithm

     Convert a ‘gnutls_compression_method_t’ value to a string.

     *Returns:* a pointer to a string that contains the name of the
     specified compression algorithm, or ‘NULL’ .

gnutls_compression_list
-----------------------

 -- Function: const gnutls_compression_method_t *
          gnutls_compression_list ( VOID)

     Get a list of compression methods.

     *Returns:* a zero-terminated list of ‘gnutls_compression_method_t’
     integers indicating the available compression methods.

gnutls_global_set_mem_functions
-------------------------------

 -- Function: void gnutls_global_set_mem_functions
          (gnutls_alloc_function ALLOC_FUNC, gnutls_alloc_function
          SECURE_ALLOC_FUNC, gnutls_is_secure_function IS_SECURE_FUNC,
          gnutls_realloc_function REALLOC_FUNC, gnutls_free_function
          FREE_FUNC)
     ALLOC_FUNC: it's the default memory allocation function.  Like
     ‘malloc()’ .

     SECURE_ALLOC_FUNC: This is the memory allocation function that will
     be used for sensitive data.

     IS_SECURE_FUNC: a function that returns 0 if the memory given is
     not secure.  May be NULL.

     REALLOC_FUNC: A realloc function

     FREE_FUNC: The function that frees allocated data.  Must accept a
     NULL pointer.

     *Deprecated:* since 3.3.0 it is no longer possible to replace the
     internally used memory allocation functions

     This is the function where you set the memory allocation functions
     gnutls is going to use.  By default the libc's allocation functions
     (‘malloc()’ , ‘free()’ ), are used by gnutls, to allocate both
     sensitive and not sensitive data.  This function is provided to set
     the memory allocation functions to something other than the
     defaults

     This function must be called before ‘gnutls_global_init()’ is
     called.  This function is not thread safe.

gnutls_openpgp_privkey_sign_hash
--------------------------------

 -- Function: int gnutls_openpgp_privkey_sign_hash
          (gnutls_openpgp_privkey_t KEY, const gnutls_datum_t * HASH,
          gnutls_datum_t * SIGNATURE)
     KEY: Holds the key

     HASH: holds the data to be signed

     SIGNATURE: will contain newly allocated signature

     This function is no-op.

     *Returns:* ‘GNUTLS_E_UNIMPLEMENTED_FEATURE’ .

gnutls_priority_compression_list
--------------------------------

 -- Function: int gnutls_priority_compression_list (gnutls_priority_t
          PCACHE, const unsigned int ** LIST)
     PCACHE: is a ‘gnutls_priority_t’ type.

     LIST: will point to an integer list

     Get a list of available compression method in the priority
     structure.

     *Returns:* the number of methods, or an error code.

     *Since:* 3.0

gnutls_x509_crt_get_preferred_hash_algorithm
--------------------------------------------

 -- Function: int gnutls_x509_crt_get_preferred_hash_algorithm
          (gnutls_x509_crt_t CRT, gnutls_digest_algorithm_t * HASH,
          unsigned int * MAND)
     CRT: Holds the certificate

     HASH: The result of the call with the hash algorithm used for
     signature

     MAND: If non-zero it means that the algorithm MUST use this hash.
     May be ‘NULL’ .

     This function will read the certificate and return the appropriate
     digest algorithm to use for signing with this certificate.  Some
     certificates (i.e.  DSA might not be able to sign without the
     preferred algorithm).

     *Deprecated:* Please use
     ‘gnutls_pubkey_get_preferred_hash_algorithm()’ .

     *Returns:* the 0 if the hash algorithm is found.  A negative error
     code is returned on error.

     *Since:* 2.12.0

gnutls_x509_privkey_sign_hash
-----------------------------

 -- Function: int gnutls_x509_privkey_sign_hash (gnutls_x509_privkey_t
          KEY, const gnutls_datum_t * HASH, gnutls_datum_t * SIGNATURE)
     KEY: a key

     HASH: holds the data to be signed

     SIGNATURE: will contain newly allocated signature

     This function will sign the given hash using the private key.  Do
     not use this function directly unless you know what it is.  Typical
     signing requires the data to be hashed and stored in special
     formats (e.g.  BER Digest-Info for RSA).

     This API is provided only for backwards compatibility, and thus
     restricted to RSA, DSA and ECDSA key types.  For other key types
     please use ‘gnutls_privkey_sign_hash()’ and
     ‘gnutls_privkey_sign_data()’ .

     *Returns:* On success, ‘GNUTLS_E_SUCCESS’ (0) is returned,
     otherwise a negative error value.

     Deprecated in: 2.12.0