1 /***************************************************************************
3 * Project ___| | | | _ \| |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
8 * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel@haxx.se>, et al.
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.haxx.se/docs/copyright.html.
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
21 ***************************************************************************/
23 * An example of curl_easy_send() and curl_easy_recv() usage.
29 #include <curl/curl.h>
31 /* Auxiliary function that waits on the socket. */
32 static int wait_on_socket(curl_socket_t sockfd, int for_recv, long timeout_ms)
35 fd_set infd, outfd, errfd;
38 tv.tv_sec = timeout_ms / 1000;
39 tv.tv_usec= (timeout_ms % 1000) * 1000;
45 FD_SET(sockfd, &errfd); /* always check for error */
48 FD_SET(sockfd, &infd);
51 FD_SET(sockfd, &outfd);
54 /* select() returns the number of signalled sockets or -1 */
55 res = select(sockfd + 1, &infd, &outfd, &errfd, &tv);
63 /* Minimalistic http request */
64 const char *request = "GET / HTTP/1.0\r\nHost: example.com\r\n\r\n";
65 curl_socket_t sockfd; /* socket */
70 /* A general note of caution here: if you're using curl_easy_recv() or
71 curl_easy_send() to implement HTTP or _any_ other protocol libcurl
72 supports "natively", you're doing it wrong and you should stop.
74 This example uses HTTP only to show how to use this API, it does not
75 suggest that writing an application doing this is sensible.
78 curl = curl_easy_init();
80 curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");
81 /* Do not do the transfer - only connect to host */
82 curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 1L);
83 res = curl_easy_perform(curl);
86 printf("Error: %s\n", strerror(res));
90 /* Extract the socket from the curl handle - we'll need it for waiting.
91 * Note that this API takes a pointer to a 'long' while we use
92 * curl_socket_t for sockets otherwise.
94 res = curl_easy_getinfo(curl, CURLINFO_LASTSOCKET, &sockextr);
97 printf("Error: %s\n", curl_easy_strerror(res));
101 sockfd = (curl_socket_t)sockextr;
103 /* wait for the socket to become ready for sending */
104 if(!wait_on_socket(sockfd, 0, 60000L)) {
105 printf("Error: timeout.\n");
109 puts("Sending request.");
110 /* Send the request. Real applications should check the iolen
111 * to see if all the request has been sent */
112 res = curl_easy_send(curl, request, strlen(request), &iolen);
114 if(CURLE_OK != res) {
115 printf("Error: %s\n", curl_easy_strerror(res));
118 puts("Reading response.");
120 /* read the response */
124 wait_on_socket(sockfd, 1, 60000L);
125 res = curl_easy_recv(curl, buf, 1024, &iolen);
130 nread = (curl_off_t)iolen;
132 printf("Received %" CURL_FORMAT_CURL_OFF_T " bytes.\n", nread);
136 curl_easy_cleanup(curl);