docs/libcurl/opts/CURLOPT_SEEKDATA.3

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.TH CURLOPT_SEEKDATA 3 "November 04, 2020" "libcurl 7.78.0" "curl_easy_setopt options"

.SH NAME
CURLOPT_SEEKDATA \- custom pointer passed to the seek callback
.SH SYNOPSIS
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_SEEKDATA, void *pointer);
.SH DESCRIPTION
Data \fIpointer\fP to pass to the seek callback function. If you use the
\fICURLOPT_SEEKFUNCTION(3)\fP option, this is the pointer you'll get as
input.
.SH DEFAULT
If you don't set this, NULL is passed to the callback.
.SH PROTOCOLS
HTTP, FTP, SFTP
.SH EXAMPLE
.nf
static int seek_cb(void *userp, curl_off_t offset, int origin)
{
  struct data *d = (struct data *)userp;
  lseek(d->our_fd, offset, origin);
  return CURL_SEEKFUNC_OK;
}

{
  struct data seek_data;
  curl_easy_setopt(CURL *handle, CURLOPT_SEEKFUNCTION, seek_cb);
  curl_easy_setopt(CURL *handle, CURLOPT_SEEKDATA, &seek_data);
}
.fi
.SH AVAILABILITY
Added in 7.18.0
.SH RETURN VALUE
.SH "SEE ALSO"
.BR CURLOPT_STDERR "(3), " CURLOPT_DEBUGFUNCTION "(3), "