---
name: "gnutls_openpgp_crt_get_auth_subkey"
section: "3"
platform: "linux"
package: "gnutls-doc"
version: "3.5.8-5+deb9u5"
release: "Debian 9 (Stretch)"
platforms: ["linux"]
url: "https://new.carta.tech/gnutls_openpgp_crt_get_auth_subkey"
---

# gnutls\_openpgp\_crt\_get\_auth\_subkey(3)

API function

## NAME

gnutls\_openpgp\_crt\_get\_auth\_subkey - API function

## SYNOPSIS

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

**int gnutls\_openpgp\_crt\_get\_auth\_subkey(gnutls\_openpgp\_crt\_t** *crt***, gnutls\_openpgp\_keyid\_t** *keyid***, unsigned int** *flag***);**

## ARGUMENTS

- gnutls\_openpgp\_crt\_t crt

  the structure that contains the OpenPGP public key.

- gnutls\_openpgp\_keyid\_t keyid

  the struct to save the keyid.

- unsigned int flag

  Non-zero indicates that a valid subkey is always returned.

## DESCRIPTION

Returns the 64-bit keyID of the first valid OpenPGP subkey marked for authentication.  If flag is non-zero and no authentication subkey exists, then a valid subkey will be returned even if it is not marked for authentication.

## RETURNS

**GNUTLS\_E\_SUCCESS** on success, or an error code.

## REPORTING BUGS

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

## COPYRIGHT

Copyright © 2001-2020 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

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