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.TH CURLOPT_PINNEDPUBLICKEY 3 "27 Aug 2014" "libcurl 7.38.0" "curl_easy_setopt options"
.SH NAME
CURLOPT_PINNEDPUBLICKEY \- set pinned public key
.SH SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PINNEDPUBLICKEY, char *pinnedpubkey);
.SH DESCRIPTION
Pass a pointer to a zero terminated string as parameter. The string should be
the file name of your pinned public key. The format expected is "PEM" or "DER".

When negotiating a TLS or SSL connection, the server sends a certificate
indicating its identity. A public key is extracted from this certificate and
if it does not exactly match the public key provided to this option, curl will
abort the connection before sending or receiving any data.
.SH DEFAULT
NULL
.SH PROTOCOLS
All TLS based protocols: HTTPS, FTPS, IMAPS, POP3, SMTPS etc.
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
  curl_easy_setopt(curl, CURLOPT_PINNEDPUBLICKEY, "/etc/publickey.der");

  /* Perform the request */
  curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
If built TLS enabled. This is currently only implemented in the OpenSSL,
GnuTLS and GSKit backends.

Added in libcurl 7.39.0
.SH RETURN VALUE
Returns CURLE_OK if TLS enabled, CURLE_UNKNOWN_OPTION if not, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.
.SH "SEE ALSO"
.BR CURLOPT_SSL_VERIFYPEER "(3), "
.BR CURLOPT_SSL_VERIFYHOST "(3), "
.BR CURLOPT_CAINFO "(3), "
.BR CURLOPT_CAPATH "(3), "