---
name: "gnutls_compress_certificate_set_methods"
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_compress_certificate_set_methods"
---

# gnutls\_compress\_certificate\_set\_methods(3)

API function

## NAME

gnutls\_compress\_certificate\_set\_methods - API function

## SYNOPSIS

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

**int gnutls\_compress\_certificate\_set\_methods(gnutls\_session\_t** *session***, const gnutls\_compression\_method\_t \*** *methods***, size\_t** *methods\_len***);**

## ARGUMENTS

- gnutls\_session\_t session

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

- const gnutls\_compression\_method\_t \* methods

  is a list of supported compression methods.

- size\_t methods\_len

  number of compression methods in  *methods*

## DESCRIPTION

This function sets the supported compression methods for certificate compression for the given session. The list of supported compression methods will be used for a) requesting the compression of peer's certificate and b) selecting the method to compress the local certificate before sending it to the peer. The order of compression methods inside the list does matter as the method that appears earlier in the list will be preferred before the later ones. Note that even if you set the list of supported compression methods, the compression might not be used if the peer does not support any of your chosen compression methods.

The list of supported compression methods must meet the following criteria: Argument  *methods* must be an array of valid compression methods of type **gnutls\_compression\_method\_t**. Argument  *methods\_len* must contain the number of compression methods stored in the  *methods* array and must be within range \<1, 127\>. The length constraints are defined by **MIN\_COMPRESS\_CERTIFICATE\_METHODS** and **MAX\_COMPRESS\_CERTIFICATE\_METHODS** macros located in the header file compress\_certificate.h.

If either  *methods* or  *methods\_len* is equal to 0, current list of supported compression methods will be unset.

## RETURNS

**GNUTLS\_E\_SUCCESS** on success, otherwise a negative error code.

Since 3.7.4

## 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/