CURLMOPT_SOCKETDATA - Man Page

#include <curl/curl.h>

CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_SOCKETDATA, void *pointer);

A data pointer to pass to the socket callback set with the CURLMOPT_SOCKETFUNCTION(3) option.

This pointer is not touched by libcurl but is only passed in as the socket callback's clientp argument.

NULL

This functionality affects all supported protocols

struct priv {
  void *ours;
};

static int sock_cb(CURL *e, curl_socket_t s, int what, void *cbp, void *sockp)
{
  struct priv *p = sockp;
  printf("my ptr: %p\n", p->ours);

  if(what == CURL_POLL_REMOVE) {
    /* remove the socket from our collection */
  }
  if(what & CURL_POLL_IN) {
    /* wait for read on this socket */
  }
  if(what & CURL_POLL_OUT) {
    /* wait for write on this socket */
  }

  return 0;
}

int main(void)
{
  struct priv setup;
  CURLM *multi = curl_multi_init();
  /* ... use socket callback and custom pointer */
  curl_multi_setopt(multi, CURLMOPT_SOCKETFUNCTION, sock_cb);
  curl_multi_setopt(multi, CURLMOPT_SOCKETDATA, &setup);
}

Added in curl 7.15.4

Returns CURLM_OK.

CURLMOPT_SOCKETFUNCTION(3), CURLMOPT_TIMERFUNCTION(3), curl_multi_socket_action(3)

CURLMOPT_SOCKETFUNCTION(3), curl_multi_setopt(3), libcurl-symbols(3).