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CURLOPT_OPENSOCKETDATA(3) curl_easy_setopt options CURLOPT_OPENSOCKETDATA(3)

NAME

CURLOPT_OPENSOCKETDATA - custom pointer passed to open socket callback

SYNOPSIS

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_OPENSOCKETDATA, void *pointer);

DESCRIPTION

Pass a pointer that will be untouched by libcurl and passed as the first argument in the opensocket callback set with CURLOPT_OPENSOCKETFUNCTION(3).

DEFAULT

The default value of this parameter is NULL.

PROTOCOLS

All

EXAMPLE

/* make libcurl use the already established socket 'sockfd' */
static curl_socket_t opensocket(void *clientp, curlsocktype purpose, struct curl_sockaddr *address) { curl_socket_t sockfd; sockfd = *(curl_socket_t *)clientp; /* the actual externally set socket is passed in via the OPENSOCKETDATA option */ return sockfd; }
static int sockopt_callback(void *clientp, curl_socket_t curlfd, curlsocktype purpose) { /* This return code was added in libcurl 7.21.5 */ return CURL_SOCKOPT_ALREADY_CONNECTED; }
curl = curl_easy_init(); if(curl) { /* libcurl will internally think that you connect to the host * and port that you specify in the URL option. */ curl_easy_setopt(curl, CURLOPT_URL, "http://99.99.99.99:9999"); /* call this function to get a socket */ curl_easy_setopt(curl, CURLOPT_OPENSOCKETFUNCTION, opensocket); curl_easy_setopt(curl, CURLOPT_OPENSOCKETDATA, &sockfd);
/* call this function to set options for the socket */ curl_easy_setopt(curl, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
res = curl_easy_perform(curl);
curl_easy_cleanup(curl); }

AVAILABILITY

Added in 7.17.1

RETURN VALUE

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

SEE ALSO

CURLOPT_OPENSOCKETFUNCTION(3), CURLOPT_SOCKOPTFUNCTION(3),
May 15, 2017 libcurl 7.60.0