.\" generated by cd2nroff 0.1 from CURLOPT_SSH_KEYDATA.md
.TH CURLOPT_SSH_KEYDATA 3 "2025-06-27" libcurl
.SH NAME
CURLOPT_SSH_KEYDATA \- pointer passed to the SSH key callback
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SSH_KEYDATA, void *pointer);
.fi
.SH DESCRIPTION
Pass a void * as parameter. This \fIpointer\fP is passed along verbatim to the
callback set with \fICURLOPT_SSH_KEYFUNCTION(3)\fP.
.SH DEFAULT
NULL
.SH PROTOCOLS
This functionality affects scp and sftp
.SH EXAMPLE
.nf
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);
  }
}
.fi
.SH AVAILABILITY
Added in curl 7.19.6
.SH RETURN VALUE
\fIcurl_easy_setopt(3)\fP returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non\-zero means an error occurred, see
\fIlibcurl\-errors(3)\fP.
.SH SEE ALSO
.BR CURLOPT_SSH_KEYDATA (3),
.BR CURLOPT_SSH_KNOWNHOSTS (3)