.TH LIBKECCAK_HMAC_INITIALISE 3 LIBKECCAK-%VERSION%
.SH NAME
libkeccak_hmac_initialise - Initialise HMAC-hashing state
.SH SYNOPSIS
.LP
.nf
#include <libkeccak.h>
.P
int libkeccak_hmac_initialise(libkeccak_hmac_state_t *\fIstate\fP,
                              const libkeccak_spec_t *\fIspec\fP,
                              const char *\fIkey\fP, size_t \fIkey_length\fP);
.fi
.P
Link with \fI-lkeccak\fP.
.SH DESCRIPTION
The
.BR libkeccak_hmac_initialise ()
function initialises \fI*state\fP and sets the algorithm
tuning parameters to those specified by \fI*spec\fP,
and the key to \fIkey\fP of length \fIkey_length\fP.
.SH RETURN VALUES
The
.BR libkeccak_hmac_initialise ()
function returns 0 upon successful completion.
On error, -1 is returned and \fIerrno\fP is set to describe
the error.
.SH ERRORS
The
.BR libkeccak_hmac_initialise ()
function may fail for any specified for the functions
.BR malloc (3)
and
.BR realloc (3).
.SH SEE ALSO
.BR libkeccak_hmac_create (3),
.BR libkeccak_hmac_destroy (3),
.BR libkeccak_hmac_fast_destroy (3),
.BR libkeccak_hmac_copy (3),
.BR libkeccak_spec_sha3 (3),
.BR libkeccak_spec_shake (3),
.BR libkeccak_spec_rawshake (3),
.BR libkeccak_spec_check (3),
.BR libkeccak_generalised_spec_initialise (3),
.BR libkeccak_state_initialise (3)
.SH AUTHORS
Principal author, Mattias Andrée.  See the LICENSE file for the full
list of authors.
.SH BUGS
Please report bugs to https://github.com/maandree/libkeccak/issues or to
maandree@member.fsf.org