CURLOPT_SOCKOPTDATA(3)

1CURLOPT_SOCKOPTDATA(3)     curl_easy_setopt options     CURLOPT_SOCKOPTDATA(3)
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NAME

6       CURLOPT_SOCKOPTDATA - custom pointer to pass to sockopt callback
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SYNOPSIS

9       #include <curl/curl.h>
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11       CURLcode   curl_easy_setopt(CURL   *handle,  CURLOPT_SOCKOPTDATA,  void
12       *pointer);
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DESCRIPTION

15       Pass a pointer that will be untouched by  libcurl  and  passed  as  the
16       first  argument  in  the sockopt callback set with CURLOPT_SOCKOPTFUNC‐
17       TION(3).
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DEFAULT

20       The default value of this parameter is NULL.
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PROTOCOLS

23       All
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EXAMPLE

26       static int sockopt_callback(void *clientp, curl_socket_t curlfd,
27                                   curlsocktype purpose)
28       {
29         int val = *(int *)clientp;
30         setsockopt(curldfd, SOL_SOCKET, SO_RCVBUF, (const char *)&val, sizeof(val));
31         return CURL_SOCKOPT_OK;
32       }
33
34       curl = curl_easy_init();
35       if(curl) {
36         int recvbuffersize = 256 * 1024;
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38         curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
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40         /* call this function to set options for the socket */
41         curl_easy_setopt(curl, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
42         curl_easy_setopt(curl, CURLOPT_SOCKOPTDATA, &recvbuffersize);
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44         res = curl_easy_perform(curl);
45
46         curl_easy_cleanup(curl);
47       }
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AVAILABILITY

50       Added in 7.16.0
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RETURN VALUE

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