curl/docs/libcurl/opts/CURLOPT_SEEKDATA.md

---

c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Title: CURLOPT_SEEKDATA Section: 3 Source: libcurl See-also:

• CURLOPT_DEBUGFUNCTION (3)
• CURLOPT_IOCTLFUNCTION (3)
• CURLOPT_SEEKFUNCTION (3)
• CURLOPT_STDERR (3) Protocol:
• All Added-in: 7.18.0 ---

NAME

CURLOPT_SEEKDATA - pointer passed to the seek callback

SYNOPSIS

#include <curl/curl.h>

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

DESCRIPTION

Data pointer to pass to the seek callback function. If you use the CURLOPT_SEEKFUNCTION(3) option, this is the pointer you get as input.

DEFAULT

If you do not set this, NULL is passed to the callback.

%PROTOCOLS%

EXAMPLE

#include <unistd.h> /* for lseek() */

struct data {
  int our_fd;
};

static int seek_cb(void *clientp, curl_off_t offset, int origin)
{
  struct data *d = (struct data *)clientp;
  lseek(d->our_fd, offset, origin);
  return CURL_SEEKFUNC_OK;
}

int main(void)
{
  struct data seek_data;
  CURL *curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_SEEKFUNCTION, seek_cb);
    curl_easy_setopt(curl, CURLOPT_SEEKDATA, &seek_data);
  }
}

%AVAILABILITY%

RETURN VALUE