---
name: "gnutls_pubkey_export"
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_pubkey_export"
---

# gnutls\_pubkey\_export(3)

API function

## NAME

gnutls\_pubkey\_export - API function

## SYNOPSIS

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

**int gnutls\_pubkey\_export(gnutls\_pubkey\_t** *key***, gnutls\_x509\_crt\_fmt\_t** *format***, void \*** *output\_data***, size\_t \*** *output\_data\_size***);**

## ARGUMENTS

- gnutls\_pubkey\_t key

  Holds the certificate

- gnutls\_x509\_crt\_fmt\_t format

  the format of output params. One of PEM or DER.

- void \* output\_data

  will contain a certificate PEM or DER encoded

- size\_t \* output\_data\_size

  holds the size of output\_data (and will be replaced by the actual size of parameters)

## DESCRIPTION

This function will export the public key to DER or PEM format. The contents of the exported data is the SubjectPublicKeyInfo X.509 structure.

If the buffer provided is not long enough to hold the output, then \*output\_data\_size is updated and **GNUTLS\_E\_SHORT\_MEMORY\_BUFFER** will be returned.

If the structure is PEM encoded, it will have a header of "BEGIN CERTIFICATE".

## RETURNS

In case of failure a negative error code will be returned, and 0 on success.

## SINCE

2\.12.0

## 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/