Tribblix: manual page: CURLMOPT

CURLMOPT_SOCKETDATA(3) Introduction to Library Functions

NAME

CURLMOPT_SOCKETDATA - custom pointer passed to the socket callback

SYNOPSIS

#include <curl/curl.h>

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

DESCRIPTION

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.

DEFAULT

NULL

PROTOCOLS

This functionality affects all supported protocols

EXAMPLE

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);
}

AVAILABILITY

Added in curl 7.15.4

RETURN VALUE

Returns CURLM_OK.