libcurl – HTTP,ftp,ssh,telnet,ldap client API

curl is a command line tool for transferring files with URL syntax, supporting FTP, FTPS, HTTP, HTTPS, SCP, SFTP, TFTP, TELNET, DICT, LDAP, LDAPS and FILE. curl supports SSL certificates, HTTP POST, HTTP PUT, FTP uploading, HTTP form based upload, proxies, cookies, user+password authentication (Basic, Digest, NTLM, Negotiate, kerberos…), file transfer resume, proxy tunneling and a busload of other useful tricks.

Quote from http://curl.haxx.se/

Advantages of using libcurl:

You do not need to read up RFC to code for HTTP post or ftp client, you just need to download libcurl-dev and try it out.

Let me show you one of the simple example source code from curl official site.

/*****************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * $Id: simple.c,v 1.6 2004/08/23 14:22:52 bagder Exp $
 */

#include &lt;stdio.h&gt;
#include &lt;curl/curl.h&gt;

int main(void)
{
  CURL *curl;
  CURLcode res;

  curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "curl.haxx.se");
    res = curl_easy_perform(curl);

    /* always cleanup */
    curl_easy_cleanup(curl);
  }
  return 0;
}

Check out the libcurl tutorial and the sample source codes.