gnutls_record_send(3) — Linux manual page


gnutls_record_send(3)            gnutls            gnutls_record_send(3)

NAME         top

       gnutls_record_send - API function

SYNOPSIS         top

       #include <gnutls/gnutls.h>

       ssize_t gnutls_record_send(gnutls_session_t session, const void *
       data, size_t data_size);

ARGUMENTS         top

       gnutls_session_t session
                   is a gnutls_session_t type.

       const void * data
                   contains the data to send

       size_t data_size
                   is the length of the data

DESCRIPTION         top

       This function has the similar semantics with send().  The only
       difference is that it accepts a GnuTLS session, and uses
       different error codes.  Note that if the send buffer is full,
       send() will block this function.  See the send() documentation
       for more information.

       You can replace the default push function which is send(), by
       using gnutls_transport_set_push_function().

       If the EINTR is returned by the internal push function then
       GNUTLS_E_AGAIN is returned, you must call this function again
       with the exact same parameters, or provide a NULL pointer for
       data and 0 for  data_size , in order to write the same data as
       before. If you wish to discard the previous data instead of
       retrying, you must call gnutls_record_discard_queued() before
       calling this function with different parameters. Note that the
       latter works only on special transports (e.g., UDP).  cf.

       Note that in DTLS this function will return the
       GNUTLS_E_LARGE_PACKET error code if the send data exceed the data
       MTU value - as returned by gnutls_dtls_get_data_mtu(). The errno
       value EMSGSIZE also maps to GNUTLS_E_LARGE_PACKET.  Note that
       since 3.2.13 this function can be called under cork in DTLS mode,
       and will refuse to send data over the MTU size by returning

RETURNS         top

       The number of bytes sent, or a negative error code.  The number
       of bytes sent might be less than  data_size .  The maximum number
       of bytes this function can send in a single call depends on the
       negotiated maximum record size.

REPORTING BUGS         top

       Report bugs to <>.
       Home page:

COPYRIGHT         top

       Copyright © 2001-2023 Free Software Foundation, Inc., and others.
       Copying and distribution of this file, with or without
       modification, are permitted in any medium without royalty
       provided the copyright notice and this notice are preserved.

SEE ALSO         top

       The full documentation for gnutls is maintained as a Texinfo
       manual.  If the /usr/share/doc/gnutls/ directory does not contain
       the HTML form visit

COLOPHON         top

       This page is part of the GnuTLS (GnuTLS Transport Layer Security
       Library) project.  Information about the project can be found at
       ⟨⟩.  If you have a bug report for this
       manual page, send it to  This page was obtained
       from the tarball gnutls-3.8.2.tar.xz fetched from
       ⟨⟩ on 2023-12-22.  If you
       discover any rendering problems in this HTML version of the page,
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       manual page), send a mail to

gnutls                            3.8.2            gnutls_record_send(3)