CURLOPT_PROXY_CAPATH(3) Library Functions Manual CURLOPT_PROXY_CAPATH(3)
NAME
CURLOPT_PROXY_CAPATH - directory holding HTTPS proxy CA certificates
SYNOPSIS
#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_PROXY_CAPATH, char *capath);
DESCRIPTION
Pass a char pointer to a null-terminated string naming a directory
holding multiple CA certificates to verify the HTTPS proxy with. If
libcurl is built against OpenSSL, the certificate directory must be
prepared using the OpenSSL c_rehash utility. This makes sense only when
CURLOPT_PROXY_SSL_VERIFYPEER(3) is enabled (which it is by default).
The application does not have to keep the string around after setting
this option.
Using this option multiple times makes the last set string override the
previous ones. Set it to NULL to disable its use again and switch back
to internal default.
The default value for this can be figured out with CURLINFO_CAPATH(3).
DEFAULT
NULL
PROTOCOLS
This functionality affects all TLS based protocols: HTTPS, FTPS, IMAPS,
POP3S, SMTPS etc.
This option works only with the following TLS backends: GnuTLS, OpenSSL
and mbedTLS
EXAMPLE
int main(void)
{
CURL *curl = curl_easy_init();
if(curl) {
CURLcode result;
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
/* using an HTTPS proxy */
curl_easy_setopt(curl, CURLOPT_PROXY, "https://proxy.example:443");
curl_easy_setopt(curl, CURLOPT_PROXY_CAPATH, "/etc/cert-dir");
result = curl_easy_perform(curl);
curl_easy_cleanup(curl);
}
}
AVAILABILITY
Added in curl 7.52.0
RETURN VALUE
CURLE_OK if supported; or an error such as:
CURLE_NOT_BUILT_IN - Not supported by the SSL backend
CURLE_UNKNOWN_OPTION
CURLE_OUT_OF_MEMORY
SEE ALSO
CURLOPT_CAINFO(3), CURLOPT_DEBUGFUNCTION(3), CURLOPT_PROXY_CAINFO(3),
CURLOPT_PROXY_SSL_VERIFYHOST(3), CURLOPT_STDERR(3)
libcurl 2026-03-23 CURLOPT_PROXY_CAPATH(3)
curl 8.19.0 - Generated Sun Mar 29 15:09:56 CDT 2026