---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: CURLOPT_TLSAUTH_USERNAME
Section: 3
Source: libcurl
See-also:
  - CURLOPT_TLSAUTH_PASSWORD (3)
  - CURLOPT_TLSAUTH_TYPE (3)
Protocol:
  - TLS
TLS-backend:
  - OpenSSL
  - GnuTLS
---

# NAME

CURLOPT_TLSAUTH_USERNAME - username to use for TLS authentication

# SYNOPSIS

~~~c
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TLSAUTH_USERNAME, char *user);
~~~

# DESCRIPTION

Pass a char pointer as parameter, which should point to the null-terminated
username to use for the TLS authentication method specified with the
CURLOPT_TLSAUTH_TYPE(3) option. Requires that the
CURLOPT_TLSAUTH_PASSWORD(3) option also be set.

The application does not have to keep the string around after setting this
option.

This feature relies in TLS SRP which does not work with TLS 1.3.

# DEFAULT

NULL

# EXAMPLE

~~~c
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
    curl_easy_setopt(curl, CURLOPT_TLSAUTH_TYPE, "SRP");
    curl_easy_setopt(curl, CURLOPT_TLSAUTH_USERNAME, "user");
    curl_easy_setopt(curl, CURLOPT_TLSAUTH_PASSWORD, "secret");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}
~~~

# AVAILABILITY

Added in 7.21.4, with the OpenSSL and GnuTLS backends only

# RETURN VALUE

Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.