NAME¶

CURLOPT_IOCTLDATA - custom pointer passed to I/O callback

SYNOPSIS¶

#include <curl/curl.h>

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

DESCRIPTION¶

Pass the pointer that will be untouched by libcurl and passed as the 3rd argument in the ioctl callback set with CURLOPT_IOCTLFUNCTION(3).

DEFAULT¶

By default, the value of this parameter is NULL.

PROTOCOLS¶

Used with HTTP

EXAMPLE¶

static curlioerr ioctl_callback(CURL *handle, int cmd, void *clientp)
{


  struct data *io = (struct data *)clientp;


  if(cmd == CURLIOCMD_RESTARTREAD) {


    lseek(fd, 0, SEEK_SET);


    current_offset = 0;


    return CURLIOE_OK;


  }


  return CURLIOE_UNKNOWNCMD;
}
{


  struct data ioctl_data;


  curl_easy_setopt(curl, CURLOPT_IOCTLFUNCTION, ioctl_callback);


  curl_easy_setopt(curl, CURLOPT_IOCTLDATA, &ioctl_data);
}

AVAILABILITY¶

Added in 7.12.3

RETURN VALUE¶

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO¶

CURLOPT_IOCTLFUNCTION(3), CURLOPT_SEEKFUNCTION(3),