gnutls_fingerprint — API function


#include <gnutls/gnutls.h>
int gnutls_fingerprint( gnutls_digest_algorithm_t algo,
  const gnutls_datum_t * data,
  void * result,
  size_t * result_size);


gnutls_digest_algorithm_t algo

is a digest algorithm

const gnutls_datum_t * data

is the data

void * result

is the place where the result will be copied (may be null).

size_t * result_size

should hold the size of the result. The actual size of the returned result will also be copied there.


This function will calculate a fingerprint (actually a hash), of the given data. The result is not printable data. You should convert it to hex, or to something else printable.

This is the usual way to calculate a fingerprint of an X.509 DER encoded certificate. Note however that the fingerprint of an OpenPGP certificate is not just a hash and cannot be calculated with this function.


On success, GNUTLS_E_SUCCESS (0) is returned, otherwise an error code is returned.


Report bugs to <>.

General guidelines for reporting bugs:

GnuTLS home page:


The full documentation for gnutls is maintained as a Texinfo manual. If the info and gnutls programs are properly installed at your site, the command

info gnutls

should give you access to the complete manual. As an alternative you may obtain the manual from:


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