---
name: "gnutls_alpn_set_protocols"
section: "3"
platform: "linux"
package: "gnutls"
version: "3.8.13-3"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/gnutls_alpn_set_protocols"
---

# gnutls\_alpn\_set\_protocols(3)

API function

## NAME

gnutls\_alpn\_set\_protocols - API function

## SYNOPSIS

**#include \<gnutls/gnutls.h\>**

**int gnutls\_alpn\_set\_protocols(gnutls\_session\_t** *session***, const gnutls\_datum\_t \*** *protocols***, unsigned** *protocols\_size***, unsigned int** *flags***);**

## ARGUMENTS

- gnutls\_session\_t session

  is a **gnutls\_session\_t** type.

- const gnutls\_datum\_t \* protocols

  is the protocol names to add.

- unsigned protocols\_size

  the number of protocols to add.

- unsigned int flags

  zero or a sequence of **gnutls\_alpn\_flags\_t**

## DESCRIPTION

This function is to be used by both clients and servers, to declare the supported ALPN protocols, which are used during negotiation with peer.

See **gnutls\_alpn\_flags\_t** description for the documentation of available flags.

## RETURNS

On success, **GNUTLS\_E\_SUCCESS** (0) is returned, otherwise a negative error code is returned.

Since 3.2.0

## REPORTING BUGS

Report bugs to \<bugs@gnutls.org\>.\
 Home page: https://www.gnutls.org

## COPYRIGHT

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

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

- https://www.gnutls.org/manual/