CURLOPT_SSH_KEYDATA(3) - Man pages

CURLOPT_SSH_KEYDATA(3)      Library Functions Manual     CURLOPT_SSH_KEYDATA(3)

NAME
       CURLOPT_SSH_KEYDATA - pointer passed to the SSH key callback

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSH_KEYDATA, void *pointer);

DESCRIPTION
       Pass a void * as parameter. This pointer is passed along verbatim to the
       callback set with CURLOPT_SSH_KEYFUNCTION(3).

DEFAULT
       NULL

PROTOCOLS
       This functionality affects scp and sftp

EXAMPLE
       struct mine {
         void *custom;
       };
       static int keycb(CURL *easy,
                        const struct curl_khkey *knownkey,
                        const struct curl_khkey *foundkey,
                        enum curl_khmatch match,
                        void *clientp)
       {
         /* 'clientp' points to the callback_data struct */
         /* investigate the situation and return the correct value */
         return CURLKHSTAT_FINE_ADD_TO_FILE;
       }

       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           struct mine callback_data;
           curl_easy_setopt(curl, CURLOPT_URL, "sftp://example.com/thisfile.txt");
           curl_easy_setopt(curl, CURLOPT_SSH_KEYFUNCTION, keycb);
           curl_easy_setopt(curl, CURLOPT_SSH_KEYDATA, &callback_data);
           curl_easy_setopt(curl, CURLOPT_SSH_KNOWNHOSTS, "/home/user/known_hosts");

           curl_easy_perform(curl);
         }
       }

AVAILABILITY
       Added in curl 7.19.6

RETURN VALUE
       curl_easy_setopt(3) returns a CURLcode indicating success or error.

       CURLE_OK  (0) means everything was OK, non-zero means an error occurred,
       see libcurl-errors(3).

SEE ALSO
       CURLOPT_SSH_KEYDATA(3), CURLOPT_SSH_KNOWNHOSTS(3)

libcurl                            2026-07-12            CURLOPT_SSH_KEYDATA(3)

Generated by dwww version 1.16 on Sat Oct 3 05:45:53 CEST 2026.