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.TH CURLOPT_SSLKEY 3 "January 02, 2023" "libcurl 7.88.1" "curl_easy_setopt options"

.SH NAME
CURLOPT_SSLKEY \- private key file for TLS and SSL client cert
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSLKEY, char *keyfile);
.fi
.SH DESCRIPTION
Pass a pointer to a null-terminated string as parameter. The string should be
the file name of your private key. The default format is "PEM" and can be
changed with \fICURLOPT_SSLKEYTYPE(3)\fP.

(Windows, iOS and Mac OS X) This option is ignored by Secure Transport and
Schannel SSL backends because they expect the private key to be already present
in the key-chain or PKCS#12 file containing the certificate.

The application does not have to keep the string around after setting this
option.
.SH DEFAULT
NULL
.SH PROTOCOLS
All TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, 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_SSLCERT, "client.pem");
  curl_easy_setopt(curl, CURLOPT_SSLKEY, "key.pem");
  curl_easy_setopt(curl, CURLOPT_KEYPASSWD, "s3cret");
  ret = curl_easy_perform(curl);
  curl_easy_cleanup(curl);
}
.fi
.SH AVAILABILITY
If built TLS enabled.
.SH RETURN VALUE
Returns CURLE_OK if TLS is supported, CURLE_UNKNOWN_OPTION if not, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.
.SH "SEE ALSO"
.BR CURLOPT_SSLKEYTYPE "(3), " CURLOPT_SSLCERT "(3), "