- Introducing curl_easy_send() and curl_easy_recv(). They can be used to send

and receive data over a connection previously setup with curl_easy_perform()
  and its CURLOPT_CONNECT_ONLY option. The sendrecv.c example was added to
  show how they can be used.

docs/examples/sendrecv.c

@@ -0,0 +1,117 @@
+/*****************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * An example of curl_easy_send() and curl_easy_recv() usage.
+ *
+ * $Id$
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <curl/curl.h>
+
+/* Auxiliary function that waits on the socket. */
+static int wait_on_socket(int sockfd, int for_recv, long timeout_ms)
+{
+  struct timeval tv;
+  long seconds, usecs;
+  fd_set infd, outfd, errfd;
+  int res;
+
+  tv.tv_sec = timeout_ms / 1000;
+  tv.tv_usec= (timeout_ms % 1000) * 1000;
+
+  FD_ZERO(&infd);
+  FD_ZERO(&outfd);
+  FD_ZERO(&errfd);
+
+  FD_SET(sockfd, &errfd); /* always check for error */
+
+  if(for_recv)
+  {
+    FD_SET(sockfd, &infd);
+  }
+  else
+  {
+    FD_SET(sockfd, &outfd);
+  }
+
+  /* select() returns the number of signalled sockets or -1 */
+  res = select(sockfd + 1, &infd, &outfd, &errfd, &tv);
+  return res;
+}
+
+int main(void)
+{
+  CURL *curl;
+  CURLcode res;
+  /* Minimalistic http request */
+  const char *request = "GET / HTTP/1.0\r\nHost: curl.haxx.se\r\n\r\n";
+  int sockfd; /* socket */
+  size_t iolen;
+
+  curl = curl_easy_init();
+  if(curl) {
+    curl_easy_setopt(curl, CURLOPT_URL, "curl.haxx.se");
+    /* Do not do the transfer - only connect to host */
+    curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 1L);
+    res = curl_easy_perform(curl);
+
+    if(CURLE_OK != res)
+    {
+      printf("Error: %s\n", strerror(res));
+      return 1;
+    }
+
+    /* Extract the socket from the curl handle - we'll need it
+     * for waiting */
+    res = curl_easy_getinfo(curl, CURLINFO_LASTSOCKET, &sockfd);
+
+    if(CURLE_OK != res)
+    {
+      printf("Error: %s\n", strerror(res));
+      return 1;
+    }
+
+    /* wait for the socket to become ready for sending */
+    if(!wait_on_socket(sockfd, 0, 60000L))
+    {
+      printf("Error: timeout.\n");
+      return 1;
+    }
+
+    puts("Sending request.");
+    /* Send the request. Real applications should check the iolen
+     * to see if all the request has been sent */
+    res = curl_easy_send(curl, request, strlen(request), &iolen);
+
+    if(CURLE_OK != res)
+    {
+      printf("Error: %s\n", strerror(res));
+      return 1;
+    }
+    puts("Reading response.");
+
+    /* read the response */
+    for(;;)
+    {
+      char buf[1024];
+
+      wait_on_socket(sockfd, 1, 60000L);
+      res = curl_easy_recv(curl, buf, 1024, &iolen);
+
+      if(CURLE_OK != res)
+        break;
+
+      printf("Received %u bytes.\n", iolen);
+    }
+
+    /* always cleanup */
+    curl_easy_cleanup(curl);
+  }
+  return 0;
+}