NAME

CURLOPT_IOCTLDATA - 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 is 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

#include <unistd.h> /* for lseek */
struct data {


  int fd; /* our file descriptor */
};
static curlioerr ioctl_callback(CURL *handle, int cmd, void *clientp)
{


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


  if(cmd == CURLIOCMD_RESTARTREAD) {


    lseek(io->fd, 0, SEEK_SET);


    return CURLIOE_OK;


  }


  return CURLIOE_UNKNOWNCMD;
}
int main(void)
{


  struct data ioctl_data;


  CURL *curl = curl_easy_init();


  if(curl) {


    curl_easy_setopt(curl, CURLOPT_IOCTLFUNCTION, ioctl_callback);


    curl_easy_setopt(curl, CURLOPT_IOCTLDATA, &ioctl_data);


  }
}

AVAILABILITY

Added in 7.12.3. Deprecated since 7.18.0.

RETURN VALUE

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