libcurl的使用

libcurl的使用

flyfish

libcurl is a free and easy-to-use client-side URL transfer library,
supporting DICT, FILE, FTP, FTPS, Gopher, HTTP, HTTPS, IMAP, IMAPS,
LDAP, LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMTP, SMTPS, Telnet
and TFTP. libcurl 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, http proxy tunneling and more!

libcurl is highly portable, it builds and works identically on
numerous platforms, including Solaris, NetBSD, FreeBSD, OpenBSD,
Darwin, HPUX, IRIX, AIX, Tru64, Linux, UnixWare, HURD, Windows, Amiga,
OS/2, BeOs, Mac OS X, Ultrix, QNX, OpenVMS, RISC OS, Novell NetWare,
DOS and more…

libcurl is free, thread-safe, IPv6 compatible, feature rich, well
supported, fast, thoroughly documented and is already used by many
known, big and successful companies and numerous applications.

官网
https://curl.haxx.se/libcurl/

libcurl是一个免费的易于使用的客户端URL传输库
支持 DICT, FILE, FTP, FTPS, Gopher, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMTP, SMTPS, Telnet and TFTP
支持SSL certificates, HTTP POST, HTTP PUT, FTP uploading, HTTP 表单上传, proxies, cookies, user+password authentication，文件传输断点续传，HTTP代理隧道

libcurl是免费的，线程安全的，兼容IPV6，有丰富特性，支持良好，快速，彻底的文档。libcurl已经被许多知名的大企业以及应用程序所采用。

环境
VC2013 update5
Win7 x64

编译 以debug版本为例
下载存放地址E:libcurl README文件所在目录

打开文件
curlprojectsWindowsVC12curl-all.sln
直接编译

生成的libcurld.lib和libcurld.dll的路径是
curluildWin32VC12DLL Debug

配置

打开项目属性页对话框
配置属性-》C/C++-》常规附加包含目录
E:libcurlinclude

配置属性-》链接器-》常规-》附加库目录
E:libcurluildWin32VC12DLL Debug

配置属性-》链接器-》输入
libcurld.lib

示例
https

  CURL *curl;
  CURLcode res;

  curl_global_init(CURL_GLOBAL_DEFAULT);

  curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");

#ifdef SKIP_PEER_VERIFICATION
    /*
     * If you want to connect to a site who isn"t using a certificate that is
     * signed by one of the certs in the CA bundle you have, you can skip the
     * verification of the server"s certificate. This makes the connection
     * A LOT LESS SECURE.
     *
     * If you have a CA cert for the server stored someplace else than in the
     * default bundle, then the CURLOPT_CAPATH option might come handy for
     * you.
     */
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
#endif

#ifdef SKIP_HOSTNAME_VERIFICATION
    /*
     * If the site you"re connecting to uses a different host name that what
     * they have mentioned in their server certificate"s commonName (or
     * subjectAltName) fields, libcurl will refuse to connect. You can skip
     * this check, but this will make the connection less secure.
     */
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
#endif

    /* Perform the request, res will get the return code */
    res = curl_easy_perform(curl);
    /* Check for errors */
    if(res != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s
",
              curl_easy_strerror(res));

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

  curl_global_cleanup();

POST

  CURL *curl;
  CURLcode res;

  /* In windows, this will init the winsock stuff */
  curl_global_init(CURL_GLOBAL_ALL);

  /* get a curl handle */
  curl = curl_easy_init();
  if(curl) {
    /* First set the URL that is about to receive our POST. This URL can
       just as well be a https:// URL if that is what should receive the
       data. */
    curl_easy_setopt(curl, CURLOPT_URL, "http://postit.example.com/moo.cgi");
    /* Now specify the POST data */
    curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "name=daniel&project=curl");

    /* Perform the request, res will get the return code */
    res = curl_easy_perform(curl);
    /* Check for errors */
    if(res != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s
",
              curl_easy_strerror(res));

    /* always cleanup */
    curl_easy_cleanup(curl);
  }
  curl_global_cleanup();