gnutls\_x509\_crt\_set\_key\_purpose\_oid(3) gnutls gnutls\_x509\_crt\_set\_key\_purpose\_oid(3)

# [NAME](#NAME)

gnutls\_x509\_crt\_set\_key\_purpose\_oid - API function

# [SYNOPSIS](#SYNOPSIS)

**#include <gnutls/x509.h>**

**int gnutls\_x509\_crt\_set\_key\_purpose\_oid(gnutls\_x509\_crt\_t cert, const void * oid, unsigned int critical);**

# [ARGUMENTS](#ARGUMENTS)

[gnutls\_x509\_crt\_t cert](#gnutls_x509_crt_t)

a certificate of type **gnutls\_x509\_crt\_t**

[const void * oid](#const)

a pointer to a null terminated string that holds the OID

[unsigned int critical](#unsigned)

Whether this extension will be critical or not

# [DESCRIPTION](#DESCRIPTION)

This function will set the key purpose OIDs of the Certificate. These are stored in the Extended Key Usage extension (2.5.29.37) See the GNUTLS\_KP\_* definitions for human readable names.

Subsequent calls to this function will append OIDs to the OID list.

# [RETURNS](#RETURNS)

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

# [REPORTING BUGS](#REPORTING_BUGS)

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

# [COPYRIGHT](#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](#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/](https://www.gnutls.org/manual/)

3.8.13 gnutls

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Document: gnutls_x509_crt_set_key_purpose_oid(3) from gnutls 3.8.13-r1 (Chainguard OS)
Source: https://gitlab.com/gnutls/gnutls