{"id":118797,"date":"2026-10-28T05:18:48","date_gmt":"2026-10-27T21:18:48","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/118797.html"},"modified":"2026-10-28T05:18:48","modified_gmt":"2026-10-27T21:18:48","slug":"linux-%e7%bd%91%e7%bb%9c%e5%a5%97%e6%8e%a5%e5%ad%97%e7%bc%96%e7%a8%8b%ef%bc%88%e4%ba%8c%ef%bc%89%e4%bb%8e-0-%e5%88%b0-1-%e5%ae%9e%e7%8e%b0-udp-%e5%9b%9e%e5%a3%b0%e6%9c%8d%e5%8a%a1%e5%99%a8%ef%bc%8crec","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/118797.html","title":{"rendered":"Linux \u7f51\u7edc\u5957\u63a5\u5b57\u7f16\u7a0b\uff08\u4e8c\uff09\u4ece 0 \u5230 1 \u5b9e\u73b0 UDP \u56de\u58f0\u670d\u52a1\u5668\uff0crecvfrom\uff0csendto"},"content":{"rendered":"

\/* MD \/ \u5bcc\u6587\u672c\u4e2d\u7684 .toc\uff08\u542b\u535a\u5ba2\u56ed\u642c\u5bb6\u7b49\u5d4c\u5957\u7ed3\u6784\uff09\uff1b.toc-box \u5728\u4fa7\u680f\uff0c\u4e0d\u53d7\u5f71\u54cd *\/
\n #content_views .toc,
\n \/* \u7f16\u8f91\u5668\u5e38\u5728\u76ee\u5f55\u524d\u540e\u63d2\u5165\u7a7a p\uff08:empty \u4ecd\u5360 20px\uff09\uff0c\u4e00\u5e76\u53bb\u6389\u907f\u514d\u9876\u7a7a\u9699 *\/
\n #content_views.markdown_views > p:empty:has(+ .toc),
\n #content_views.markdown_views > .toc + p:empty,
\n \/* \u5bcc\u6587\u672c\u65e7\u7248\u76ee\u5f55\u6807\u8bb0 *\/
\n #content_views.htmledit_views #main-toc,
\n #content_views.htmledit_views #hr-toc,
\n #content_views.htmledit_views p[id*=\\”-toc\\”] {
\n display: none !important;
\n }
\n \/* \u76ee\u5f55\u53bb\u6389\u540e\uff0c\u7d27\u8ddf\u7684\u9996\u4e2a\u6807\u9898\u4e0d\u518d\u591a\u51fa\u4e00\u5757\u4e0a\u8fb9\u8ddd *\/
\n #content_views.markdown_views > .toc + h1,
\n #content_views.markdown_views > .toc + h2,
\n #content_views.markdown_views > .toc + h3,
\n #content_views.markdown_views > .toc + h4,
\n #content_views.markdown_views > .toc + p:empty + h1,
\n #content_views.markdown_views > .toc + p:empty + h2,
\n #content_views.markdown_views > .toc + p:empty + h3,
\n #content_views.markdown_views > .toc + p:empty + h4 {
\n margin-top: 0 !important;
\n }<\/p>\n

\u76ee\u5f55<\/p>\n

\u8bbe\u8ba1\u903b\u8f91<\/p>\n

\u8bbe\u8ba1\u76ee\u7684<\/p>\n

\u4ee3\u7801\u7ed3\u6784<\/p>\n

EchoServer.hpp\u00a0\u670d\u52a1\u7aef\u5934\u6587\u4ef6<\/p>\n

1. \u5934\u6587\u4ef6\u9632\u62a4\u4e0e\u4f9d\u8d56\u5f15\u5165<\/p>\n

2. \u79c1\u6709\u6210\u5458\u53d8\u91cf<\/p>\n

IP \u5730\u5740\u548c\u7aef\u53e3\u53f7\u5728 UDP \u901a\u4fe1\u4e2d\u7684\u4f5c\u7528<\/p>\n

\u8bbe\u8ba1\u6539\u52a8<\/p>\n

3. \u5168\u5c40\u5e38\u91cf\u4e0e\u679a\u4e3e\u9519\u8bef\u7801<\/p>\n

4. \u6784\u9020\u51fd\u6570\u4e0e\u6790\u6784\u51fd\u6570<\/p>\n

5. Init () \u670d\u52a1\u7aef\u521d\u59cb\u5316\u51fd\u6570<\/p>\n

\u91cd\u8bc6Socket<\/p>\n

6.\u00a0Start () \u4e1a\u52a1\u5faa\u73af\u542f\u52a8\u51fd\u6570<\/p>\n

recvfrom \u7cfb\u7edf\u8c03\u7528<\/p>\n

sendto \u7cfb\u7edf\u8c03\u7528<\/p>\n

EchoServerMain.cc \u670d\u52a1\u7aef\u5165\u53e3\u6587\u4ef6<\/p>\n

\u8fd0\u884c\u670d\u52a1\u7aef :<\/p>\n

EchoClient.cc \u5ba2\u6237\u7aef\u6587\u4ef6 :<\/p>\n

\u5ba2\u6237\u7aef\u4e0e\u670d\u52a1\u7aef\u7684\u6838\u5fc3\u5f02\u540c<\/p>\n

1. \u5934\u6587\u4ef6\u4e0e\u4f7f\u7528\u63d0\u793a\u51fd\u6570<\/p>\n

2. \u4e3b\u51fd\u6570\u5165\u53e3 & \u542f\u52a8\u53c2\u6570<\/p>\n

3. \u521b\u5efa socket<\/p>\n

4. \u6784\u5efa\u670d\u52a1\u7aef socket \u76ee\u6807\u5730\u5740<\/p>\n

5. \u5faa\u73af\u4ea4\u4e92\u903b\u8f91<\/p>\n

\u8fd0\u884c\u7ed3\u679c :<\/p>\n

\u672c\u5730\u56de\u73af\u5730\u5740\u901a\u4fe1 (127.0.0.1)<\/p>\n

\u5185\u7f51 IP \u901a\u4fe1 (10.0.16.7)<\/p>\n

\u516c\u7f51 IP \u901a\u4fe1 (124.222.191.171)<\/p>\n

\u5b8c\u6574\u4ee3\u7801 :<\/p>\n

\u6a21\u578b\u56fe:<\/p>\n

\u603b\u7ed3:<\/p>\n

\n

\u672c\u6587\u6211\u4eec\u5c06\u57fa\u4e8e C++ \u5b9e\u73b0\u4e00\u4e2a\u7ecf\u5178\u7684 UDP \u56de\u58f0\u670d\u52a1\u5668，\u901a\u8fc7\u6784\u5efa\u4e00\u5957\u5b8c\u6574\u7684\u5ba2\u6237\u7aef \/ \u670d\u52a1\u7aef(Server\/Client) \u901a\u4fe1\u6a21\u578b，\u628a\u7406\u8bba\u77e5\u8bc6\u8f6c\u5316\u4e3a\u53ef\u8fd0\u884c\u7684\u5de5\u7a0b\u4ee3\u7801\u3002<\/p>\n

\u8bbe\u8ba1\u903b\u8f91<\/h2>\n

\u7b80\u5355\u6765\u8bf4，UDP \u5ba2\u6237\u7aef\u548c\u670d\u52a1\u7aef\u901a\u4fe1，\u5c31\u50cf\u4e24\u4e2a\u4eba\u4e92\u76f8\u53d1\u77ed\u4fe1，\u5ba2\u6237\u7aef\u4ee3\u8868\u7528\u6237，\u670d\u52a1\u7aef\u4ee3\u8868\u5b98\u65b9\u670d\u52a1\u5668，\u5ba2\u6237\u7aef\u5411\u670d\u52a1\u7aef\u53d1\u6d88\u606f，\u670d\u52a1\u7aef\u6536\u5230\u6d88\u606f\u540e\u518d\u56de\u7ed9\u5ba2\u6237\u7aef\u3002<\/p>\n

\u6211\u4eec\u8fd9\u4e2a\u7a0b\u5e8f\u7684\u6574\u4e2a\u6d41\u7a0b，\u7528\u6700\u76f4\u767d\u7684\u8bdd\u8bb2\u5c31\u662f\u8fd9\u6837：<\/p>\n

\"\"<\/p>\n

\u8bbe\u8ba1\u76ee\u7684<\/h2>\n

\u6211\u4eec\u9009\u62e9 UDP \u56de\u58f0\u670d\u52a1\u5668\u4f5c\u4e3a\u5165\u95e8\u5b9e\u6218\u6848\u4f8b，\u6838\u5fc3\u6709\u4e24\u70b9\u8bbe\u8ba1\u8003\u91cf：<\/p>\n

1. \u8d34\u5408 UDP \u534f\u8bae\u672c\u8d28：UDP \u662f\u65e0\u8fde\u63a5\u3001\u9762\u5411\u6570\u636e\u62a5\u7684\u4f20\u8f93\u534f\u8bae，\u65e0\u9700\u4e09\u6b21\u63e1\u624b\u5efa\u7acb\u8fde\u63a5，\u901a\u4fe1\u903b\u8f91\u7b80\u5355\u3002\u9002\u5408\u56de\u58f0\u670d\u52a1\u5668\u300c\u6536\u4ec0\u4e48\u3001\u56de\u4ec0\u4e48\u300d\u7684\u6838\u5fc3\u903b\u8f91，\u80fd\u5b8c\u5168\u805a\u7126 UDP \u539f\u751f\u901a\u4fe1\u6d41\u7a0b，\u907f\u5f00 TCP \u590d\u6742\u7684\u8fde\u63a5\u7ba1\u7406\u3001\u72b6\u6001\u7ef4\u62a4，\u8ba9\u6211\u4eec\u4e13\u6ce8\u7406\u89e3socket\u3001bind\u3001recvfrom\u3001sendto\u56db\u5927\u6838\u5fc3\u63a5\u53e3\u7684\u8bbe\u8ba1\u7528\u9014\u4e0e\u8c03\u7528\u65f6\u5e8f\u3002<\/p>\n<\/p>\n

2. \u6784\u5efa\u6807\u51c6\u5316 C\/S \u901a\u4fe1\u6a21\u578b：\u9879\u76ee\u62c6\u5206\u670d\u52a1\u7aef\u4e0e\u5ba2\u6237\u7aef\u53cc\u6a21\u5757，\u590d\u523b\u7f51\u7edc\u7f16\u7a0b\u6700\u57fa\u7840\u7684\u67b6\u6784\u8303\u5f0f，\u6e05\u6670\u533a\u5206\u670d\u52a1\u7aef\u88ab\u52a8\u76d1\u542c\u4e0e\u5ba2\u6237\u7aef\u4e3b\u52a8\u53d1\u8d77\u7684\u89d2\u8272\u5dee\u5f02，\u76f4\u89c2\u5448\u73b0\u65e0\u8fde\u63a5\u534f\u8bae\u4e0b\u4e24\u7aef\u7684\u4ea4\u4e92\u6d41\u7a0b，\u4e3a\u540e\u7eed TCP \u7f16\u7a0b\u3001\u9ad8\u5e76\u53d1\u7f51\u7edc\u6846\u67b6\u5b66\u4e60\u6253\u4e0b\u57fa\u7840\u3002<\/p>\n

\u4ee3\u7801\u7ed3\u6784<\/h2>\n

\u56e0\u4e3a\u8fd9\u4e2a\u5c0f\u9879\u76ee\u662f\u7ecf\u5178\u7684 \u5ba2\u6237\u7aef – \u670d\u52a1\u7aef \u7ed3\u6784，\u6240\u4ee5\u6211\u4eec\u5c31\u9700\u8981\u5728\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u7aef\u5206\u522b\u521b\u5efa\u6587\u4ef6\u7f16\u5199\u4ee3\u7801，\u53c8\u56e0\u4e3a\u670d\u52a1\u7aef\u5f80\u5f80\u6bd4\u5ba2\u6237\u7aef\u66f4\u590d\u6742\u70b9，\u6240\u4ee5\u5728\u670d\u52a1\u7aef\u6211\u4eec\u5c31\u4f7f\u7528\u4e24\u4e2a\u6587\u4ef6 (EchoServer.hpp + EchoServerMain.cc)，\u5728\u5ba2\u6237\u7aef\u4e2d\u6211\u4eec\u5c31\u53ea\u4f7f\u7528 (EchoClient.cc) \u8fd9\u4e00\u4e2a\u6587\u4ef6<\/p>\n

\"\"<\/p>\n

\u4e09\u4e2a\u6587\u4ef6\u5404\u81ea\u8d1f\u8d23\u4ec0\u4e48?<\/p>\n

EchoServer.hpp \u670d\u52a1\u7aef\u5934\u6587\u4ef6 :<\/p>\n

1. \u8fd9\u4e2a\u6587\u4ef6\u662f\u6574\u4e2a UDP \u670d\u52a1\u7aef\u7684 \u201c\u6838\u5fc3\u5b9a\u4e49\u4ed3\u5e93\u201d\u3002\u56e0\u4e3a\u6211\u4eec\u8981\u628a UDP \u670d\u52a1\u7aef\u5c01\u88c5\u6210\u4e00\u4e2a\u7c7b，\u4e3a\u4ec0\u4e48?\u00a0<\/p>\n<\/p>\n

2. \u5982\u679c\u6211\u4eec\u4e0d\u5199\u7c7b，\u628a\u6240\u6709\u4ee3\u7801\u90fd\u5806\u5728 main \u51fd\u6570\u91cc\u5168\u90e8\u6df7\u5728\u4e00\u8d77\u3002\u4ee5\u540e\u5982\u679c\u60f3\u6539\u7aef\u53e3\u3001\u6539\u65e5\u5fd7\u3001\u590d\u7528\u670d\u52a1\u7aef\u4ee3\u7801，\u5c31\u4f1a\u53d1\u73b0\u4ee3\u7801\u4e71\u6210\u4e00\u56e2\u3002\u800c\u5c01\u88c5\u6210 UdpServer \u7c7b\u4e4b\u540e，\u6574\u4e2a\u903b\u8f91\u53d8\u5f97\u975e\u5e38\u6e05\u6670：\u6784\u9020\u51fd\u6570\u521d\u59cb\u5316，Init() \u8d1f\u8d23\u521b\u5efa，Start() \u8d1f\u8d23\u8dd1\u6574\u4e2a\u4ee3\u7801\u903b\u8f91，\u6790\u6784\u51fd\u6570\u8d1f\u8d23\u91ca\u653e\u8d44\u6e90，\u5bf9\u5916\u6765\u770b，\u4f7f\u7528\u8005\u53ea\u9700\u8981\u521b\u5efa\u5bf9\u8c61，\u8c03\u7528 Init ()，\u8c03\u7528 Start ()，\u4e0d\u7528\u5173\u5fc3\u5e95\u5c42 socket \u600e\u4e48\u521b\u5efa\u3001bind \u600e\u4e48\u5931\u8d25\u3001\u9519\u8bef\u600e\u4e48\u6253\u5370\u3002<\/p>\n<\/p>\n

3. \u8fd9\u5c31\u662f\u9762\u5411\u5bf9\u8c61\u6700\u6838\u5fc3\u7684\u597d\u5904：\u4f7f\u7528\u8005\u548c\u5b9e\u73b0\u8005\u89e3\u8026\u3002\u5728\u4ee5\u540e\u7684\u771f\u5b9e\u5f00\u53d1\u91cc\u597d\u5904\u66f4\u660e\u663e：\u4e00\u4e2a\u7c7b\u7ba1\u7406\u4e00\u4e2a\u670d\u52a1，\u5b9e\u73b0\u8f7b\u677e\u590d\u7528\u3002\u00a0<\/p>\n

EchoServerMain.cc \u670d\u52a1\u7aef\u5165\u53e3\u6587\u4ef6 :<\/p>\n

\u8fd9\u4e2a\u6587\u4ef6\u662f\u670d\u52a1\u7aef\u7684 \u201c\u542f\u52a8\u5165\u53e3\u201d，\u4e5f\u662f\u4e3b\u51fd\u6570\u6240\u5728\u6587\u4ef6\u3002\u5b83\u4e0d\u5199\u4efb\u4f55\u590d\u6742\u7684\u7f51\u7edc\u903b\u8f91，\u53ea\u505a\u4e09\u4ef6\u4e8b：(1). \u5f15\u5165\u5934\u6587\u4ef6 #include "EchoServer.hpp" ; (2). \u89e3\u6790\u547d\u4ee4\u884c\u53c2\u6570，\u62ff\u5230\u7528\u6237\u4f20\u5165\u7684\u7aef\u53e3 ; (3). \u521b\u5efa UdpServer \u5bf9\u8c61，\u8c03\u7528 Init() \u521d\u59cb\u5316\u3001Start() \u542f\u52a8\u670d\u52a1\u3002\u7b80\u5355\u8bf4：\u5934\u6587\u4ef6\u8d1f\u8d23 \u201c\u9020\u96f6\u4ef6\u3001\u5b9a\u89c4\u5219\u201d，main \u6587\u4ef6\u8d1f\u8d23 \u201c\u7ec4\u88c5\u96f6\u4ef6\u3001\u542f\u52a8\u7a0b\u5e8f\u201d，\u8fd9\u5c31\u662f C++ \u6807\u51c6\u7684\u58f0\u660e\u4e0e\u5b9e\u73b0\u5206\u79bb\u5199\u6cd5\u3002<\/p>\n

EchoClient.cc \u5ba2\u6237\u7aef\u6587\u4ef6 :<\/p>\n

\u5ba2\u6237\u7aef\u903b\u8f91\u5c31\u76f8\u5bf9\u7b80\u5355，\u4e0d\u9700\u8981\u590d\u6742\u7684\u7c7b\u5c01\u88c5\u548c\u63a5\u53e3\u62c6\u5206，\u6240\u4ee5\u6211\u4eec\u76f4\u63a5\u7528\u4e00\u4e2a\u6587\u4ef6\u641e\u5b9a\u5168\u90e8\u529f\u80fd\u3002\u8fd9\u4e2a\u6587\u4ef6\u5305\u542b\u5ba2\u6237\u7aef\u7684\u4e3b\u51fd\u6570\u3001\u547d\u4ee4\u884c\u53c2\u6570\u6821\u9a8c\u3001socket \u521b\u5efa\u3001\u4e3b\u52a8\u53d1\u9001\u6570\u636e\u3001\u63a5\u6536\u670d\u52a1\u7aef\u56de\u663e\u7684\u5b8c\u6574\u6d41\u7a0b，\u7528\u6237\u8fd0\u884c\u540e\u76f4\u63a5\u5c31\u80fd\u548c\u670d\u52a1\u7aef\u901a\u4fe1\u3002<\/p>\n

Mkefile \u7f16\u8bd1\u6587\u4ef6 :<\/p>\n

\"\"<\/h2>\n

\u4e0b\u9762\u6211\u4eec\u76f4\u63a5\u770b\u670d\u52a1\u7aef EchoServer.hpp \u7684\u4ee3\u7801 :<\/p>\n

EchoServer.hpp\u00a0\u670d\u52a1\u7aef\u5934\u6587\u4ef6<\/h2>\n

\u8fd9\u4e2a\u6587\u4ef6\u662f\u6574\u4e2a UDP \u670d\u52a1\u7aef\u7684\u6838\u5fc3\u5c01\u88c5，\u6211\u4eec\u5728\u8fd9\u91cc\u5b9a\u4e49 UdpServer \u7c7b\u3001\u9519\u8bef\u679a\u4e3e\u3001\u4f9d\u8d56\u5934\u6587\u4ef6，\u628a\u7f51\u7edc\u521d\u59cb\u5316\u3001\u7aef\u53e3\u7ed1\u5b9a\u3001\u5faa\u73af\u6536\u53d1\u7684\u903b\u8f91\u5168\u90e8\u5c01\u88c5\u6210\u7c7b\u7684\u6210\u5458\u65b9\u6cd5，\u5b9e\u73b0\u529f\u80fd\u548c\u5165\u53e3\u89e3\u8026\u3002<\/p>\n

\"\"<\/p>\n

1. \u5934\u6587\u4ef6\u9632\u62a4\u4e0e\u4f9d\u8d56\u5f15\u5165<\/h3>\n

\u4f5c\u4e3a C++ \u5de5\u7a0b\u7684\u6807\u51c6\u89c4\u8303，\u6211\u4eec\u9996\u5148\u505a\u4e24\u4ef6\u4e8b：<\/p>\n<\/p>\n

1. \u4f7f\u7528 #ifndef \/ #define \/ #endif \u5934\u6587\u4ef6\u4fdd\u62a4，\u9632\u6b62\u5934\u6587\u4ef6\u88ab\u91cd\u590d\u5305\u542b，\u907f\u514d\u7f16\u8bd1\u51b2\u7a81； 2. \u5f15\u5165\u6240\u6709\u4f9d\u8d56\u7684\u7cfb\u7edf\u5934\u6587\u4ef6\u3001\u65e5\u5fd7\u6a21\u5757\u3001\u547d\u540d\u7a7a\u95f4，\u56e0\u4e3a\u6211\u4eec\u5728\u6253\u5370\u65f6\u7528\u5230\u4e86\u524d\u9762\u5b66\u5230\u7684 Logger.hpp \u65e5\u5fd7\u7c7b\u7684\u65b9\u4fbf\u6211\u4eec\u8fdb\u884c\u6253\u5370，\u6240\u4ee5\u6211\u4eec\u4e5f\u8981\u5305\u542b\u65e5\u5fd7\u7c7b\u5934\u6587\u4ef6\u3002<\/p>\n

2. \u79c1\u6709\u6210\u5458\u53d8\u91cf<\/h3>\n

\u5728\u8bb2\u7c7b\u7684\u529f\u80fd\u4e4b\u524d，\u6211\u4eec\u5148\u660e\u786e\u8fd9\u4e2a\u7c7b\u5185\u90e8\u8981\u5b58\u4ec0\u4e48\u6570\u636e：<\/p>\n<\/p>\n

\"\"<\/p>\n

_sockfd \u672c\u8d28\u662f\u64cd\u4f5c\u7cfb\u7edf\u63d0\u4f9b\u7ed9\u6211\u4eec\u7684\u7f51\u7edc\u901a\u4fe1 \u201c\u64cd\u4f5c\u53e5\u67c4\u201d\u3002\u6211\u4eec\u540e\u9762\u521b\u5efa socket\u3001\u7ed1\u5b9a\u7aef\u53e3\u3001\u6536\u53d1\u6570\u636e\u3001\u5168\u9760\u8fd9\u4e2a\u6587\u4ef6\u63cf\u8ff0\u7b26\u3002\u628a\u5b83\u8bbe\u4e3a\u79c1\u6709，\u907f\u514d\u5916\u90e8\u4ee3\u7801\u968f\u610f\u4fee\u6539\u3002<\/p>\n<\/p>\n

_port \u662f\u5b58\u50a8\u670d\u52a1\u7aef\u7684\u7aef\u53e3\u53f7\u3002UDP \u670d\u52a1\u7aef\u5fc5\u987b\u5148\u56fa\u5b9a\u7aef\u53e3，\u5ba2\u6237\u7aef\u624d\u80fd\u7cbe\u51c6\u627e\u5230\u670d\u52a1\u7aef\u3002\u79c1\u6709\u5316\u540e，\u7aef\u53e3\u53ea\u80fd\u901a\u8fc7\u6784\u9020\u51fd\u6570\u521d\u59cb\u5316，\u8fd0\u884c\u4e2d\u65e0\u6cd5\u88ab\u4fee\u6539\u3002<\/p>\n

IP \u5730\u5740\u548c\u7aef\u53e3\u53f7\u5728 UDP \u901a\u4fe1\u4e2d\u7684\u4f5c\u7528<\/h4>\n

1. \u5728 UDP \u8fd9\u79cd\u65e0\u8fde\u63a5\u901a\u4fe1\u6a21\u578b\u91cc，IP + \u7aef\u53e3\u53f7 = \u552f\u4e00\u7684\u901a\u4fe1\u7aef\u70b9\u3002<\/p>\n<\/p>\n

2. IP \u5730\u5740\u8d1f\u8d23\u5b9a\u4f4d\u4e3b\u673a<\/span>，\u5b83\u7684\u4f5c\u7528\u5c31\u662f\u5c31\u662f\u5728\u4e92\u8054\u7f51\u7684\u832b\u832b\u4e3b\u673a\u91cc，\u7cbe\u51c6\u627e\u5230\u76ee\u6807\u670d\u52a1\u5668\u8fd9\u53f0\u673a\u5668\u672c\u8eab\u3002\u5ba2\u6237\u7aef\u901a\u8fc7 IP，\u5c31\u80fd\u786e\u5b9a\u6570\u636e\u8981\u53d1\u5230\u54ea\u4e00\u53f0\u670d\u52a1\u5668；\u670d\u52a1\u7aef\u901a\u8fc7 IP \u6536\u5230\u6570\u636e，\u7136\u540e\u8fdb\u884c\u5904\u7406\u3002\u6240\u4ee5 IP \u89e3\u51b3\u7684\u662f\u6570\u636e\u8be5\u53d1\u7ed9\u54ea\u53f0\u7535\u8111\u3002<\/p>\n<\/p>\n

3. \u7aef\u53e3\u53f7port\u8d1f\u8d23\u5b9a\u4f4d\u8fdb\u7a0b<\/span>，\u56e0\u4e3a\u4e00\u53f0\u670d\u52a1\u5668\u4e0a\u53ef\u80fd\u540c\u65f6\u8dd1\u7740\u51e0\u5341\u4e0a\u767e\u4e2a\u7a0b\u5e8f，\u5b83\u4eec\u90fd\u7528\u540c\u4e00\u4e2a IP，\u64cd\u4f5c\u7cfb\u7edf\u6b63\u5f0f\u4f9d\u9760\u7aef\u53e3\u53f7\u624d\u80fd\u533a\u5206\u6570\u636e\u5230\u5e95\u8be5\u4ea4\u7ed9\u54ea\u4e2a\u8fdb\u7a0b\u3002\u6211\u4eec\u7684 UDP \u670d\u52a1\u7aef\u56fa\u5b9a\u76d1\u542c\u4e00\u4e2a\u7aef\u53e3，\u6bd4\u5982 8080，\u5c31\u662f\u544a\u8bc9\u64cd\u4f5c\u7cfb\u7edf\u6240\u6709\u53d1\u5230 8080 \u7aef\u53e3\u7684\u6570\u636e，\u5168\u90e8\u4ea4\u7ed9\u6211\u8fd9\u4e2a\u8fdb\u7a0b\u5904\u7406；\u5ba2\u6237\u7aef\u5fc5\u987b\u4e25\u683c\u5bf9\u5e94\u8fd9\u4e2a\u7aef\u53e3\u53f7，\u4e0d\u7136\u5c31\u7b97 IP \u5bf9\u4e86，\u7aef\u53e3\u4e0d\u5bf9，\u6570\u636e\u4e5f\u5230\u4e0d\u4e86\u6211\u4eec\u7684\u670d\u52a1\u7aef\u3002\u6240\u4ee5\u7aef\u53e3\u89e3\u51b3\u7684\u95ee\u9898\u662f\u6570\u636e\u5230\u4e86\u7535\u8111\u540e，\u8be5\u4ea4\u7ed9\u54ea\u4e2a\u7a0b\u5e8f\u3002<\/p>\n

\u8bbe\u8ba1\u6539\u52a8<\/h4>\n

\u4f46\u662f\u8fd9\u91cc\u8865\u5145\u4e00\u70b9\u6211\u5728\u5199\u4ee3\u7801\u65f6\u7684\u8bbe\u8ba1\u6539\u52a8：<\/p>\n

1. \u5728\u6700\u5f00\u59cb\u7684\u8bbe\u8ba1\u91cc，\u79c1\u6709\u6210\u5458\u4e2d\u6211\u4eec\u989d\u5916\u52a0\u8fc7\u4e00\u4e2a\u7528\u6765\u4fdd\u5b58 IP \u5730\u5740\u7684\u6210\u5458\u53d8\u91cf，\u672c\u610f\u662f\u60f3\u8ba9\u670d\u52a1\u7aef\u7ed1\u5b9a\u4e00\u4e2a\u56fa\u5b9a IP\u3002\u4f46\u5728\u5b9e\u9645\u6d4b\u8bd5\u4e2d\u53d1\u73b0\u5199\u6b7b\u67d0\u4e2a\u5177\u4f53 IP \u7684\u8fd9\u79cd\u5199\u6cd5\u9650\u5236\u592a\u5927，\u4e3a\u4ec0\u4e48\u5462?<\/p>\n

2. \u8fd9\u91cc\u6211\u4eec\u8981\u5148\u5398\u6e05\u4e00\u4e2a\u5bb9\u6613\u6df7\u6dc6\u7684\u5173\u952e\u70b9：IP \u5728\u5b8f\u89c2\u89c6\u89d2\u548c\u5fae\u89c2\u89c6\u89d2\u4e0b，\u5bf9\u5e94\u5bf9\u8c61\u662f\u4e0d\u4e00\u6837\u7684\u3002\u5b8f\u89c2\u5c42\u9762，\u6211\u4eec\u8bf4 IP \u5bf9\u5e94\u4e00\u53f0\u4e3b\u673a\u3002\u5728\u6574\u4e2a\u4e92\u8054\u7f51\u73af\u5883\u4e2d，IP \u5730\u5740\u5c31\u662f\u4e00\u53f0\u670d\u52a1\u5668\u7684\u552f\u4e00\u6807\u8bc6，\u5ba2\u6237\u7aef\u901a\u8fc7\u76ee\u6807 IP，\u5c31\u80fd\u8de8\u8d8a\u7f51\u7edc，\u627e\u5230\u5bf9\u5e94\u7684\u90a3\u53f0\u4e3b\u673a，\u5b8c\u6210\u4e3b\u673a\u7ea7\u522b\u7684\u5bfb\u5740\u3002\u8fd9\u662f\u6211\u4eec\u65e5\u5e38\u4ea4\u6d41\u3001\u7f51\u7edc\u901a\u4fe1\u91cc\u6700\u5e38\u8bf4\u7684\u6982\u5ff5\u3002<\/p>\n

3. \u4f46\u843d\u5230\u6211\u4eec\u4ee3\u7801\u8fd9\u4e2a\u5fae\u89c2\u5c42\u9762( \u6bd4\u5982\u8bf4\u5728 bind() \u51fd\u6570\u7ed1\u5b9a\u64cd\u4f5c\u65f6)，IP \u5b9e\u9645\u5bf9\u5e94\u7684\u662f\u4e3b\u673a\u4e0a\u7684\u67d0\u4e00\u5f20\u7f51\u5361\u3002\u4e00\u53f0\u670d\u52a1\u5668\u4e3b\u673a\u53ef\u4ee5\u914d\u7f6e\u591a\u5f20\u7f51\u5361，\u6bcf\u5f20\u7f51\u5361\u90fd\u62e5\u6709\u72ec\u7acb\u7684 IP：\u672c\u673a\u56de\u73af\u7f51\u5361\u3001\u5185\u7f51\u7f51\u5361\u3001\u516c\u7f51\u7f51\u5361，\u5b83\u4eec\u90fd\u5c5e\u4e8e\u540c\u4e00\u53f0\u4e3b\u673a，\u5374\u662f\u4e09\u4e2a\u5b8c\u5168\u72ec\u7acb\u7684\u7f51\u7edc\u5165\u53e3\u3002<\/span>\u5f53\u6211\u4eec\u5728\u4ee3\u7801\u91cc\u5199\u6b7b\u7ed1\u5b9a\u67d0\u4e00\u4e2a\u5177\u4f53 IP \u65f6，\u672c\u8d28\u662f\u544a\u8bc9\u64cd\u4f5c\u7cfb\u7edf：\u6211\u8fd9\u4e2a\u8fdb\u7a0b，\u53ea\u80fd\u76d1\u542c\u8fd9\u4e00\u5f20\u7f51\u5361\u4e0a\u6536\u5230\u7684\u6570\u636e，\u5176\u4ed6\u7f51\u5361\u7684\u6570\u636e，\u7cfb\u7edf\u4f1a\u76f4\u63a5\u4e22\u5f03，\u4e0d\u4f1a\u4ea4\u7ed9\u6211\u4eec\u7684\u7a0b\u5e8f\u3002<\/p>\n

4. \u641e\u61c2\u4e86\u5b8f\u89c2 IP \u548c\u5fae\u89c2 IP \u7684\u533a\u522b，\u6211\u4eec\u518d\u5bf9\u5e94\u770b\u4e09\u79cd IP \u548c\u300c\u6211\u4eec\u7684\u7535\u8111\u3001\u4e91\u670d\u52a1\u5668\u3001Linux \u7cfb\u7edf\u300d\u7684\u5173\u7cfb，\u5c31\u7279\u522b\u597d\u7406\u89e3\u4e86：<\/p>\n

\"\"<\/p>\n

\"\"<\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0(1). \u7b2c\u4e00\u79cd\u662f\u672c\u673a\u56de\u73af IP : 127.0.0.1，\u5b83\u548c\u5916\u90e8\u7f51\u7edc\u6ca1\u5173\u7cfb，\u53ea\u5c5e\u4e8e\u5f53\u524d\u6b63\u5728\u8fd0\u884c\u7684\u64cd\u4f5c\u7cfb\u7edf\u81ea\u5df1\u3002\u4e0d\u7ba1\u662fWindows \u7535\u8111，\u8fd8\u662f Linux \u4e91\u670d\u52a1\u5668，\u7cfb\u7edf\u90fd\u4f1a\u81ea\u5e26\u8fd9\u4e2a IP\u3002\u5b83\u7684\u4f5c\u7528\u5c31\u662f\u7cfb\u7edf\u5185\u90e8\u81ea\u5df1\u548c\u81ea\u5df1\u901a\u4fe1，\u53ea\u80fd\u672c\u673a\u81ea\u6d4b，\u522b\u7684\u7535\u8111\u3001\u5916\u7f51\u90fd\u8bbf\u95ee\u4e0d\u4e86\u3002<\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0(2). \u7b2c\u4e8c\u79cd\u662f\u5185\u7f51 IP : 10.0.16.7，\u5b83\u662f\u540c\u4e00\u5c40\u57df\u7f51\u91cc\u5404\u4e2a\u8bbe\u5907\u7684\u4e13\u7528\u5730\u5740\u3002\u6bd4\u5982\u8bf4\u5bb6\u7528\u7535\u8111\u8fde WiFi \u62ff\u5230\u7684\u5185\u7f51 IP，\u53ea\u80fd\u548c\u5bb6\u91cc\u5176\u4ed6\u8bbe\u5907\u4e92\u76f8\u8bbf\u95ee；\u4e91\u670d\u52a1\u5668\u7684\u5185\u7f51 IP，\u53ea\u80fd\u548c\u540c\u673a\u623f\u3001\u540c\u5185\u7f51\u7684\u5176\u4ed6\u670d\u52a1\u5668\u901a\u4fe1\u3002\u7b80\u5355\u8bf4：\u5185\u7f51 IP \u53ea\u5728 \u201c\u540c\u4e00\u4e2a\u5c40\u57df\u7f51\u201d \u91cc\u751f\u6548，\u51fa\u4e86\u8fd9\u4e2a\u5c0f\u5708\u5b50\u5c31\u7528\u4e0d\u4e86\u3002<\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0(3). \u7b2c\u4e09\u79cd\u662f\u516c\u7f51 IP : 124.222.191.171，\u662f\u4e92\u8054\u7f51\u4e0a\u552f\u4e00\u7684\u5730\u5740\u3002\u4e91\u670d\u52a1\u5668\u516c\u7f51 IP，\u5c31\u662f\u5b83\u5728\u5168\u7f51\u7684\u8eab\u4efd\u6807\u8bc6\u3002\u5168\u4e16\u754c\u4efb\u4f55\u5730\u65b9\u7684\u7535\u8111\u3001\u624b\u673a，\u53ea\u8981\u8054\u7f51，\u90fd\u80fd\u901a\u8fc7\u8fd9\u4e2a IP \u627e\u5230\u4f60\u7684 Linux \u670d\u52a1\u5668\u3002\u5b83\u662f\u4e91\u670d\u52a1\u5668\u548c\u5916\u754c\u7f51\u7edc\u6c9f\u901a\u7684\u552f\u4e00\u901a\u9053\u3002<\/p>\n

5. \u660e\u767d\u4e86\u8fd9\u4e00\u70b9，\u6211\u4eec\u518d\u56de\u5934\u770b\u4ee3\u7801\u7684\u8bbe\u8ba1\u6539\u52a8，\u903b\u8f91\u5c31\u5b8c\u5168\u901a\u987a\u4e86：\u5982\u679c\u6211\u4eec\u5728\u4ee3\u7801\u91cc\u5199\u6b7b\u7ed1\u5b9a\u67d0\u4e00\u4e2a IP，\u5c31\u7b49\u4e8e\u7ed9\u81ea\u5df1\u7684\u670d\u52a1\u8bbe\u4e86\u9650\u5236：\u7ed1\u5b9a\u56de\u73af IP，\u5c31\u53ea\u80fd\u672c\u673a\u6d4b\u8bd5；\u7ed1\u5b9a\u5185\u7f51 IP，\u5c31\u53ea\u80fd\u5c40\u57df\u7f51\u8bbf\u95ee；\u7ed1\u5b9a\u516c\u7f51 IP，\u5c31\u53ea\u80fd\u5916\u7f51\u8fde\u63a5\u3002<\/span>\u4e0d\u7ba1\u7ed1\u5b9a\u54ea\u4e00\u4e2a，\u90fd\u4f1a\u635f\u5931\u53e6\u5916\u4e24\u79cd\u8bbf\u95ee\u65b9\u5f0f\u3002 \u6240\u4ee5\u6700\u7ec8\u6211\u4eec\u5220\u6389\u4e86 IP \u76f8\u5173\u7684\u6210\u5458\u53d8\u91cf，\u6539\u7528 INADDR_ANY<\/span>\u3002\u6539\u6210 INADDR_ANY \u4e4b\u540e，\u6211\u4eec\u7684\u5ba2\u6237\u7aef\u53ef\u4ee5\u6839\u636e\u81ea\u5df1\u6240\u5728\u7684\u7f51\u7edc\u73af\u5883，\u81ea\u7531\u9009\u62e9\u4f7f\u7528\u672c\u673a\u56de\u73af IP\u3001\u5185\u7f51 IP\u3001\u516c\u7f51 IP \u4e2d\u7684\u4efb\u610f\u4e00\u4e2a\u6765\u8fde\u63a5\u670d\u52a1\u7aef，\u4e09\u79cd\u65b9\u5f0f\u5168\u90e8\u90fd\u80fd\u6b63\u5e38\u901a\u4fe1，\u670d\u52a1\u7aef\u4e0d\u7528\u505a\u989d\u5916\u4fee\u6539\u3002<\/p>\n

6. \u8fd9\u4e5f\u662f\u4e3a\u4ec0\u4e48\u79c1\u6709\u6210\u5458\u91cc\u6211\u4eec\u53ea\u4fdd\u7559\u7aef\u53e3\u3001\u53bb\u6389 IP\u3002\u7aef\u53e3\u662f\u670d\u52a1\u5bf9\u5916\u56fa\u5b9a\u7684\u5165\u53e3\u6807\u8bc6，\u5fc5\u987b\u56fa\u5b9a；\u800c IP \u53ea\u662f\u7f51\u7edc\u5165\u53e3，\u670d\u52a1\u7aef\u672c\u6765\u5c31\u8be5\u63a5\u6536\u6240\u6709\u6765\u6e90\u7684\u8bf7\u6c42，\u4e0d\u9700\u8981\u9501\u6b7b\u67d0\u4e00\u5f20\u7f51\u5361\u3001\u67d0\u4e00\u4e2a IP\u3002<\/p>\n

3. \u5168\u5c40\u5e38\u91cf\u4e0e\u679a\u4e3e\u9519\u8bef\u7801<\/h3>\n

\"\"<\/p>\n

\u5728\u6b63\u5f0f\u5b9a\u4e49\u670d\u52a1\u7aef\u7c7b\u4e4b\u524d，\u6211\u4eec\u8fd8\u9700\u8981\u7edf\u4e00\u5168\u5c40\u5e38\u91cf\u4e0e\u9519\u8bef\u679a\u4e3e，\u6211\u4eec\u8bbe\u7f6e\u9ed8\u8ba4\u65e0\u6548\u6587\u4ef6\u63cf\u8ff0\u7b26default_fd = -1\u3001\u9ed8\u8ba4\u76d1\u542c\u7aef\u53e3default_port = 8888\u3002<\/p>\n

\u679a\u4e3e\u9519\u8bef\u7801\u5b9a\u4e49\u4e86\u53ef\u80fd\u51fa\u73b0\u7684\u5404\u7c7b\u5f02\u5e38\u72b6\u6001，\u5305\u542bSUCCESS\u6b63\u5e38\u72b6\u6001\u3001USAGE_ERR\u53c2\u6570\u9519\u8bef\u3001SOCKET_ERR\u5957\u63a5\u5b57\u521b\u5efa\u5931\u8d25\u3001BIND_ERR\u7aef\u53e3\u7ed1\u5b9a\u5931\u8d25\u3002<\/p>\n

4. \u6784\u9020\u51fd\u6570\u4e0e\u6790\u6784\u51fd\u6570<\/h3>\n

\"\"<\/p>\n

\u6784\u9020\u51fd\u6570 UdpServe \u8d1f\u8d23\u5bf9\u8c61\u521d\u59cb\u5316，\u63a5\u6536\u7528\u6237\u4f20\u5165\u7684\u7aef\u53e3，\u82e5\u7528\u6237\u672a\u6307\u5b9a\u7aef\u53e3，\u5219\u81ea\u52a8\u4f7f\u7528\u6211\u4eec\u5b9a\u4e49\u7684\u9ed8\u8ba4\u7aef\u53e3 8888，\u540c\u65f6\u5c06\u5957\u63a5\u5b57\u6587\u4ef6\u63cf\u8ff0\u7b26\u521d\u59cb\u5316\u4e3adefault_fd = -1，\u6807\u8bb0\u5957\u63a5\u5b57\u5c1a\u672a\u521b\u5efa\u3002<\/p>\n

\u6790\u6784\u51fd\u6570~UdpServer() \u8d1f\u8d23\u7a0b\u5e8f\u9000\u51fa\u65f6\u7684\u8d44\u6e90\u81ea\u52a8\u56de\u6536，\u6838\u5fc3\u6267\u884c close(_sockfd) \u64cd\u4f5c\u3002\u91ca\u653e\u5957\u63a5\u5b57\u6587\u4ef6\u63cf\u8ff0\u7b26，\u5b8c\u6210\u64cd\u4f5c\u7cfb\u7edf\u8d44\u6e90\u7684\u5b89\u5168\u56de\u6536\u3002<\/p>\n

\u8fd9\u91cc\u91cd\u70b9\u89e3\u91ca\u4e00\u4e0b fd（\u6587\u4ef6\u63cf\u8ff0\u7b26） \u7684\u5e95\u5c42\u672c\u8d28：\u5728 Linux \u64cd\u4f5c\u7cfb\u7edf\u91cc，\u4e00\u5207\u7686\u6587\u4ef6\u3002\u4e0d\u7ba1\u662f\u666e\u901a\u6587\u672c\u6587\u4ef6\u3001\u7ba1\u9053\u3001\u8bbe\u5907\u3001\u8fd8\u662f\u6211\u4eec\u8fd9\u91cc\u7684\u7f51\u7edc socket，\u64cd\u4f5c\u7cfb\u7edf\u90fd\u4f1a\u7edf\u4e00\u628a\u5b83\u4eec\u5f53\u6210\u6587\u4ef6\u6765\u7ba1\u7406\u3002\u800c fd（\u6587\u4ef6\u63cf\u8ff0\u7b26) \u672c\u8d28\u5c31\u662f\u64cd\u4f5c\u7cfb\u7edf\u5206\u914d\u7684\u4e00\u4e2a\u6574\u6570\u7f16\u53f7\u3002<\/span>\u540e\u7eed\u6240\u6709\u5bf9\u7f51\u7edc\u7684\u64cd\u4f5c \u2014\u2014 \u521b\u5efa socket\u3001bind \u7ed1\u5b9a\u3001recvfrom \u6536\u6570\u636e\u3001sendto \u53d1\u6570\u636e\u3001close \u5173\u95ed，\u5168\u9760\u8fd9\u4e2a\u6574\u6570\u7f16\u53f7\u544a\u8bc9\u64cd\u4f5c\u7cfb\u7edf\u8981\u64cd\u4f5c\u7684\u662f\u54ea\u4e00\u4e2a\u7f51\u7edc\u5bf9\u8c61\u3002fd = -1 \u4ee3\u8868\u65e0\u6548\u3001\u672a\u521b\u5efa\u3001\u672a\u6253\u5f00；fd \u2265 0 \u4ee3\u8868\u64cd\u4f5c\u7cfb\u7edf\u5df2\u7ecf\u6210\u529f\u5206\u914d\u4e86\u4e00\u4e2a\u7f51\u7edc\u901a\u4fe1\u5bf9\u8c61，\u53ef\u4ee5\u6b63\u5e38\u4f7f\u7528\u3002\u4e00\u822c\u60c5\u51b5\u4e0b\u6211\u4eec\u521b\u5efa\u51fa\u6765\u7684 sockfd \u662f 3\u3002<\/p>\n

5. Init () \u670d\u52a1\u7aef\u521d\u59cb\u5316\u51fd\u6570<\/h3>\n

\"\"<\/p>\n

\u9996\u5148\u5728\u8fd9\u4e2a Init() \u521d\u59cb\u5316\u51fd\u6570\u4e2d\u5305\u62ec\u4e86\u4e09\u4e2a\u6b65\u9aa4 : 1.\u00a0\u521b\u5efa socket ; 2. \u586b\u5145\u7f51\u7edc\u5730\u5740\u4fe1\u606f ; 3.\u00a0bind \u7ed1\u5185\u6838 socket\u3002<\/p>\n

\u6211\u4eec\u5148\u770b\u7b2c\u4e00\u6b65\u521b\u5efa socket :<\/p>\n

\"\"1. \u4e0a\u4e00\u7bc7\u6587\u7ae0\u4e2d\u6211\u4eec\u4e5f\u8bb2\u8fc7 socket() \u662f\u4e00\u4e2a\u7cfb\u7edf\u8c03\u7528，\u4f5c\u7528\u662f\u5411\u5185\u6838\u7533\u8bf7\u521b\u5efa\u4e00\u4e2a\u7f51\u7edc\u4e13\u7528\u7684 socket \u6587\u4ef6\u5bf9\u8c61，\u6210\u529f\u540e\u8fd4\u56de\u6587\u4ef6\u63cf\u8ff0\u7b26 fd\u3002<\/p>\n<\/p>\n

2. \u7b2c\u4e00\u4e2a\u53c2\u6570 AF_INET \u6307\u5b9aIPv4 \u5730\u5740\u534f\u8bae\u65cf<\/span>，\u4ee3\u8868\u6211\u4eec\u4f7f\u7528\u7ecf\u5178\u7684 IPv4 \u7f51\u7edc\u901a\u4fe1；<\/p>\n<\/p>\n

3. \u7b2c\u4e8c\u4e2a\u53c2\u6570 SOCK_DGRAM \u6307\u5b9aUDP \u65e0\u8fde\u63a5\u6570\u636e\u62a5\u5957\u63a5\u5b57<\/span>，\u4ee3\u8868\u6211\u4eec\u91c7\u7528 UDP \u534f\u8bae\u901a\u4fe1，\u7279\u70b9\u662f\u65e0\u8fde\u63a5\u3001\u9762\u5411\u6570\u636e\u5305\u3001\u4e0d\u4fdd\u8bc1\u53ef\u9760\u4f20\u8f93；<\/p>\n<\/p>\n

4. \u7b2c\u4e09\u4e2a\u53c2\u6570 0 \u5bf9\u5e94\u534f\u8bae\u7f16\u53f7，\u5f53\u524d\u573a\u666f\u4e0b\u586b 0，\u7cfb\u7edf\u4f1a\u81ea\u52a8\u5339\u914d UDP \u534f\u8bae\u3002<\/p>\n<\/p>\n

5. \u8c03\u7528 socket \u51fd\u6570\u540e，\u5185\u6838\u4f1a\u5728\u5185\u5b58\u4e2d\u521b\u5efa socket \u7f51\u7edc\u6587\u4ef6\u3001\u5206\u914d fd \u5e76\u8fd4\u56de\u3002\u6211\u4eec\u5224\u65ad\u8fd4\u56de\u503c\u662f\u5426\u5c0f\u4e8e 0：\u5c0f\u4e8e 0 \u4ee3\u8868\u521b\u5efa\u5931\u8d25，\u6253\u5370\u81f4\u547d\u65e5\u5fd7\u5e76\u9000\u51fa\u7a0b\u5e8f；\u5927\u4e8e\u7b49\u4e8e 0 \u4ee3\u8868\u521b\u5efa\u6210\u529f，\u62ff\u5230\u6709\u6548 fd，\u540e\u7eed\u6240\u6709\u7f51\u7edc\u64cd\u4f5c\u90fd\u5c06\u901a\u8fc7\u8fd9\u4e2a fd \u5b8c\u6210\u3002<\/p>\n

\u4e0b\u6765\u7b2c\u4e8c\u6b65\u5c31\u662f\u586b\u5145\u7f51\u7edc\u5730\u5740\u4fe1\u606f，\u51c6\u5907\u7ed1\u5b9a\u53c2\u6570:4<\/p>\n

\"\"<\/p>\n

\u4e3a\u4ec0\u4e48\u6211\u4eec\u8981\u586b\u5145\u7f51\u7edc\u4fe1\u606f？<\/p>\n

\u6211\u4eec\u521b\u5efa\u7684 socket \u6587\u4ef6，\u6b64\u65f6\u53ea\u662f\u4e00\u4e2a \u201c\u7a7a\u767d\u7684\u7f51\u7edc\u5bf9\u8c61\u201d，\u6ca1\u6709\u548c\u4efb\u4f55 IP\u3001\u7aef\u53e3\u5173\u8054\u3002\u586b\u5145sockaddr_in \u7ed3\u6784\u4f53，\u5c31\u662f\u7ed9\u8fd9\u4e2a socket \u51c6\u5907\u597d\u8981\u7ed1\u5b9a\u7684\u5730\u5740\u914d\u7f6e，\u544a\u8bc9\u5185\u6838\u540e\u7eed\u8981\u76d1\u542c\u54ea\u4e2a\u7aef\u53e3\u3001\u54ea\u4e9b IP \u6765\u6e90\u7684\u8bf7\u6c42，\u4e3a\u7b2c\u4e09\u6b65 bind \u7ed1\u5b9a\u505a\u53c2\u6570\u51c6\u5907\u3002<\/p>\n

\"\" sockaddr_in \u662f Linux \u7cfb\u7edf\u4e13\u95e8\u4e3aIPv4 \u534f\u8bae\u8bbe\u8ba1\u7684\u5730\u5740\u7ed3\u6784\u4f53，\u4e0a\u4e00\u7bc7\u6587\u7ae0\u4e2d\u6211\u4eec\u4e5f\u8bb2\u8fc7，\u4e13\u95e8\u7528\u6765\u5b58\u653e IP + \u7aef\u53e3\u4fe1\u606f\u3002<\/p>\n

\"\" bzero \u662f\u7cfb\u7edf\u51fd\u6570，\u4f5c\u7528\u662f\u628a\u6574\u4e2a\u7ed3\u6784\u4f53\u7684\u5185\u5b58\u5168\u90e8\u6e05\u96f6\u3002C++ \u6808\u4e0a\u521b\u5efa\u7684\u53d8\u91cf\u4f1a\u5e26\u6709\u968f\u673a\u810f\u6570\u636e，\u4e0d\u6e05\u7a7a\u4f1a\u5bfc\u81f4\u540e\u7eed\u7ed1\u5b9a\u5f02\u5e38\u3002<\/p>\n

\"\" \u518d\u6b21\u6307\u5b9a\u534f\u8bae\u65cf\u4e3a IPv4，\u5fc5\u987b\u548c\u7b2c\u4e00\u6b65 socket \u521b\u5efa\u65f6\u7684AF_INET\u4fdd\u6301\u4e00\u81f4，\u534f\u8bae\u4e0d\u5339\u914d\u4f1a\u76f4\u63a5\u5bfc\u81f4\u7ed1\u5b9a\u5931\u8d25\u3002<\/p>\n

\"\" htons() \u662f\u7f51\u7edc\u7f16\u7a0b\u6838\u5fc3\u51fd\u6570，\u5168\u79f0host to network short\u3002\u56e0\u4e3a CPU（\u4e3b\u673a）\u548c\u7f51\u7edc\u4f20\u8f93\u4f7f\u7528\u7684\u5b57\u8282\u5e8f\u76f8\u53cd：\u4e3b\u673a\u662f\u5c0f\u7aef\u5e8f，\u7f51\u7edc\u5f3a\u5236\u8981\u6c42\u5927\u7aef\u5e8f\u3002\u6211\u4eec\u5fc5\u987b\u901a\u8fc7htons，\u628a\u7528\u6237\u4f20\u5165\u7684\u4e3b\u673a\u5b57\u8282\u5e8f\u7aef\u53e3，\u8f6c\u6362\u6210\u7f51\u7edc\u80fd\u8bc6\u522b\u7684\u5b57\u8282\u5e8f，\u5426\u5219\u7aef\u53e3\u4f1a\u89e3\u6790\u9519\u8bef\u3001\u5ba2\u6237\u7aef\u65e0\u6cd5\u8fde\u63a5\u3002<\/p>\n

\"\" \u8fd9\u5c31\u662f\u6211\u4eec\u524d\u9762\u53cd\u590d\u4f18\u5316\u7684\u6700\u4f73\u5b9e\u8df5\u3002INADDR_ANY\u672c\u8d28\u662f\u4e00\u4e2a\u5b8f，\u503c\u4e3a 0，\u4ee3\u8868\u76d1\u542c\u672c\u673a\u6240\u6709\u7f51\u5361\u3001\u6240\u6709 IP \u5730\u5740\u3002\u4e0d\u7ba1\u5ba2\u6237\u7aef\u901a\u8fc7 127.0.0.1 \u672c\u673a\u3001\u5185\u7f51 IP\u3001\u516c\u7f51 IP \u8bbf\u95ee，\u53ea\u8981\u7aef\u53e3\u5339\u914d，\u6570\u636e\u90fd\u4f1a\u8def\u7531\u5230\u8fd9\u4e2a socket，\u517c\u5bb9\u5404\u79cd\u8bbf\u95ee\u573a\u666f\u3002<\/p>\n

\"\"<\/p>\n

\u8865\u5145 : \u8fd9\u91cc\u7684 local \u7ed3\u6784\u4f53，\u662f\u5b58\u653e\u5728\u7528\u6237\u6808\u5185\u5b58\u4e2d，\u53ea\u662f\u6211\u4eec\u4e34\u65f6\u51c6\u5907\u7684\u53c2\u6570，\u6b64\u65f6\u8fd8\u6ca1\u6709\u88ab\u5199\u5165\u5185\u6838，\u53ea\u6709\u7b2c\u4e09\u6b65 bind \u8c03\u7528\u540e，\u5730\u5740\u4fe1\u606f\u624d\u4f1a\u548c\u5185\u6838 socket \u6587\u4ef6\u7ed1\u5b9a\u3002<\/p>\n

\u7b2c\u4e09\u6b65\u7528\u00a0bind() \u7ed1\u5b9a，\u5c06\u5730\u5740\u4fe1\u606f\u6ce8\u518c\u5230\u5185\u6838 socket :<\/p>\n

\"\"<\/p>\n

1. bind() \u662f\u7cfb\u7edf\u8c03\u7528，\u6838\u5fc3\u4f5c\u7528\u662f\u628a\u7b2c\u4e8c\u6b65\u51c6\u5907\u597d\u7684 IP + \u7aef\u53e3\u5730\u5740\u4fe1\u606f，\u6ce8\u518c\u5230\u5185\u6838\u7684 socket \u6587\u4ef6\u5bf9\u8c61\u4e2d\u3002\u5b8c\u6210\u7ed1\u5b9a\u540e，\u64cd\u4f5c\u7cfb\u7edf\u4f1a\u5efa\u7acb\u300c\u7aef\u53e3 \u2192 socket \u6587\u4ef6\u300d\u7684\u6620\u5c04\u5173\u7cfb，\u544a\u8bc9\u5185\u6838：\u6240\u6709\u53d1\u5f80\u8fd9\u4e2a\u7aef\u53e3\u3001\u5339\u914d\u5bf9\u5e94 IP \u89c4\u5219\u7684\u6570\u636e，\u5c31\u4ea4\u7ed9\u8fd9\u4e2a socket \u6587\u4ef6\u5904\u7406，\u8fd9\u6837\u5ba2\u6237\u7aef\u5c31\u80fd\u901a\u8fc7 IP + \u7aef\u53e3\u627e\u5230\u6211\u4eec\u7684\u670d\u52a1\u7aef\u3002 2. \u7b2c\u4e00\u4e2a\u53c2\u6570 _sockfd \u5c31\u662f\u6211\u4eec\u7b2c\u4e00\u6b65\u521b\u5efa socket \u65f6\u62ff\u5230\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26，\u6307\u5b9a\u6211\u4eec\u8981\u7ed1\u5b9a\u54ea\u4e2a\u5185\u6838 socket \u5bf9\u8c61；\u7b2c\u4e8c\u4e2a\u53c2\u6570 (struct sockaddr *)&local \u662f\u5730\u5740\u53c2\u6570\u3002\u56e0\u4e3a bind \u51fd\u6570\u7684\u53c2\u6570\u8bbe\u8ba1\u8981\u6c42\u4f20\u5165\u901a\u7528\u5730\u5740\u7ed3\u6784\u4f53 sockaddr，\u6240\u4ee5\u6211\u4eec\u9700\u8981\u628a IPv4 \u4e13\u7528\u7684 sockaddr_in \u5f3a\u5236\u7c7b\u578b\u8f6c\u6362\u3002\u901a\u8fc7\u7236\u7c7b\u6307\u9488\u627e\u5230\u5b50\u7c7b\u5bf9\u8c61；\u7b2c\u4e09\u4e2a\u53c2\u6570 sizeof(local) \u662f\u5730\u5740\u7ed3\u6784\u4f53\u7684\u5927\u5c0f\u3002<\/p>\n<\/p>\n

3. bind \u51fd\u6570\u8fd4\u56de\u503c\u5c0f\u4e8e 0 \u4ee3\u8868\u7ed1\u5b9a\u5931\u8d25，\u6700\u5e38\u89c1\u539f\u56e0\u662f\u7aef\u53e3\u88ab\u5176\u4ed6\u8fdb\u7a0b\u5360\u7528，\u6211\u4eec\u6253\u5370\u65e5\u5fd7\u5e76\u9000\u51fa；\u8fd4\u56de\u503c\u5927\u4e8e\u7b49\u4e8e 0 \u4ee3\u8868\u7ed1\u5b9a\u6210\u529f，\u6b64\u65f6 socket \u6b63\u5f0f\u548c IP + \u7aef\u53e3\u5b8c\u6210\u5173\u8054，\u670d\u52a1\u7aef\u5177\u5907\u4e86\u63a5\u6536\u5ba2\u6237\u7aef\u8bf7\u6c42\u7684\u80fd\u529b\u3002<\/p>\n

\u91cd\u8bc6Socket<\/h5>\n

\u901a\u8fc7\u4e0a\u9762\u7684\u5185\u5bb9，\u6211\u4eec\u53ef\u4ee5\u4ece\u4e24\u4e2a\u5b8c\u5168\u4e0d\u540c\u7684\u7ef4\u5ea6，\u5bf9 Socket \u505a\u6700\u6e05\u6670\u7684\u603b\u7ed3：<\/p>\n

1. \u4ece\u7f51\u7edc\u901a\u4fe1\u5c42\u9762\u770b，Socket \u5c31\u662f IP + \u7aef\u53e3\u53f7\u3002\u5b83\u662f\u4e00\u4e2a\u903b\u8f91\u610f\u4e49\u4e0a\u7684\u901a\u4fe1\u7aef\u70b9，\u7528\u6765\u552f\u4e00\u6807\u8bc6\u7f51\u7edc\u4e2d\u901a\u4fe1\u7684\u53cc\u65b9\u3002\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u7aef\u4f9d\u9760\u8fd9\u4e2a\u5730\u5740\u4e92\u76f8\u5b9a\u4f4d\u3001\u5efa\u7acb\u5bf9\u8bdd，\u5b83\u662f\u62bd\u8c61\u7684\u901a\u4fe1\u8eab\u4efd，\u51b3\u5b9a\u4e86 \u201c\u8c01\u548c\u8c01\u5728\u5bf9\u8bdd\u201d\u3002<\/p>\n<\/p>\n

2. \u4ece Linux \u64cd\u4f5c\u7cfb\u7edf\u5185\u6838\u5c42\u9762\u770b，Socket \u662f\u4e00\u4e2a\u7279\u6b8a\u7684\u7f51\u7edc\u6587\u4ef6\u5bf9\u8c61\u3002\u8fdb\u7a0b\u8c03\u7528 socket () \u7cfb\u7edf\u8c03\u7528，\u5185\u6838\u4f1a\u5728\u5185\u5b58\u4e2d\u521b\u5efa\u4e00\u4e2a\u4e13\u95e8\u7528\u4e8e\u7f51\u7edc\u901a\u4fe1\u7684\u6587\u4ef6，\u5e76\u5206\u914d\u552f\u4e00\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26 fd\u3002\u8fd9\u4e2a\u6587\u4ef6\u5bf9\u8c61\u91cc\u7ef4\u62a4\u7740\u7f51\u7edc\u72b6\u6001\u3001\u534f\u8bae\u4fe1\u606f\u3001\u4ee5\u53ca\u7528\u4e8e\u6536\u53d1\u6570\u636e\u7684\u5185\u6838\u7f13\u51b2\u533a\u3002\u6211\u4eec\u4ee3\u7801\u4e2d\u6240\u6709\u7684 bind\u3001sendto\u3001recvfrom \u64cd\u4f5c，\u672c\u8d28\u4e0a\u90fd\u662f\u62ff\u7740 fd，\u5bf9\u8fd9\u4e2a\u5185\u6838\u6587\u4ef6\u5bf9\u8c61\u8fdb\u884c\u8bfb\u5199\u63a7\u5236\u3002<\/span><\/p>\n<\/p>\n

\u7b80\u5355\u6765\u8bf4：IP + \u7aef\u53e3\u662f\u5bf9\u5916\u7684\u901a\u4fe1\u8eab\u4efd，\u7528\u6765\u5bfb\u5740；Socket \u6587\u4ef6\u662f\u5bf9\u5185\u7684\u7cfb\u7edf\u8f7d\u4f53，\u7528\u6765\u6536\u53d1\u6570\u636e\u3002\u670d\u52a1\u7aef\u901a\u8fc7\u521b\u5efa\u5185\u6838\u4e2d\u7684 Socket \u6587\u4ef6，\u7ed1\u5b9a\u4e0a\u4e00\u4e2a\u516c\u5f00\u7684 IP + \u7aef\u53e3 \u5730\u5740，\u5ba2\u6237\u7aef\u51ed\u501f\u8fd9\u4e2a\u5730\u5740\u627e\u5230\u5185\u6838\u4e2d\u7684 Socket \u5bf9\u8c61，\u53cc\u65b9\u901a\u8fc7 Socket \u6587\u4ef6\u81ea\u5e26\u7684\u5185\u6838\u7f13\u51b2\u533a\u5b8c\u6210\u6570\u636e\u4ea4\u6362，\u5b9e\u73b0\u8de8\u7f51\u7edc\u901a\u4fe1\u3002<\/span><\/p>\n

6.\u00a0Start () \u4e1a\u52a1\u5faa\u73af\u542f\u52a8\u51fd\u6570<\/h3>\n

\u524d\u9762\u6211\u4eec\u901a\u8fc7 Init() \u5b8c\u6210\u4e86\u670d\u52a1\u7aef\u7684\u521d\u59cb\u5316，\u76f8\u5f53\u4e8e\u642d\u597d\u4e86\u67b6\u5b50\u3002\u800c Start() \u5c31\u662f\u670d\u52a1\u7aef\u771f\u6b63\u5f00\u59cb\u5e72\u6d3b\u3001\u6301\u7eed\u5bf9\u5916\u63d0\u4f9b\u56de\u58f0\u670d\u52a1\u7684\u6838\u5fc3\u4e1a\u52a1\u51fd\u6570\u3002\u6211\u4eec\u987a\u7740\u4ee3\u7801\u6267\u884c\u987a\u5e8f， \u628a Start() \u51fd\u6570\u62c6\u89e3\u6210 4 \u4e2a\u6838\u5fc3\u6b65\u9aa4 :<\/p>\n

\"\"<\/p>\n

\u7b2c\u4e00\u6b65\u5f00\u542fwhile()\u5faa\u73af，\u6301\u7eed\u76d1\u542c\u5ba2\u6237\u7aef\u8bf7\u6c42 :<\/p>\n

\"\"<\/p>\n

\u4e3a\u4ec0\u4e48\u7528 while(true) \u6b7b\u5faa\u73af？<\/p>\n

UDP \u670d\u52a1\u7aef\u7684\u6838\u5fc3\u7279\u6027\u662f\u88ab\u52a8\u7b49\u5f85\u5ba2\u6237\u7aef\u8fde\u63a5，\u5b83\u4e0d\u77e5\u9053\u5ba2\u6237\u7aef\u4ec0\u4e48\u65f6\u5019\u53d1\u6d88\u606f\u3001\u4f1a\u6709\u591a\u5c11\u4e2a\u5ba2\u6237\u7aef\u53d1\u6d88\u606f\u3002\u5982\u679c\u6ca1\u6709\u5faa\u73af，\u670d\u52a1\u7aef\u53ea\u4f1a\u63a5\u6536\u4e00\u6b21\u5ba2\u6237\u7aef\u6570\u636e，\u56de\u590d\u5b8c\u7a0b\u5e8f\u5c31\u7ed3\u675f\u4e86；\u5f00\u542fwhile()\u6b7b\u5faa\u73af\u540e，\u670d\u52a1\u7aef\u5c31\u4f1a\u4e00\u76f4\u4fdd\u6301\u8fd0\u884c\u72b6\u6001，\u5faa\u73af\u963b\u585e\u7b49\u5f85，\u5b9e\u73b0\u6301\u4e45\u670d\u52a1\u3002<\/p>\n

char inbuffer[1024] \u662f\u6211\u4eec\u5728\u7528\u6237\u6001\u6808\u5185\u5b58\u5b9a\u4e49\u7684\u63a5\u6536\u7f13\u51b2\u533a，\u7528\u6765\u4e34\u65f6\u5b58\u653e\u4ece\u5ba2\u6237\u7aef\u8bfb\u53d6\u5230\u7684\u6570\u636e<\/span>\u30021024 \u662f\u81ea\u5b9a\u4e49\u7684\u7f13\u51b2\u533a\u5927\u5c0f，\u51b3\u5b9a\u4e86\u5355\u6b21\u6700\u591a\u80fd\u63a5\u6536\u591a\u5c11\u5b57\u8282\u7684\u6570\u636e\u3002<\/p>\n

\u6211\u4eec\u77e5\u9053 socket() \u521b\u5efa\u597d\u4e4b\u540e\u5185\u6838\u4f1a\u81ea\u52a8\u4e3a\u8fd9\u4e2a socket \u7f51\u7edc\u6587\u4ef6\u5206\u914d\u4e24\u5757\u4e13\u5c5e\u7f13\u51b2\u533a：\u5185\u6838\u63a5\u6536\u7f13\u51b2\u533a\u548c\u5185\u6838\u53d1\u9001\u7f13\u51b2\u533a，\u7528\u6765\u6682\u5b58\u6570\u636e\u3002\u800c\u6211\u4eec\u4ee3\u7801\u91cc\u53c8\u5b9a\u4e49\u4e86\u00a0 inbuffer\u7528\u6237\u7f13\u51b2\u533a，\u8fd9\u4e24\u8005\u4e0d\u4f1a\u51b2\u7a81\u5417？<\/p>\n<\/p>\n

\u7b54\u6848\u662f\u4e0d\u51b2\u7a81，\u5b83\u4eec\u662f\u5206\u5de5\u660e\u786e\u3001\u63a5\u529b\u4f20\u9012\u7684\u5173\u7cfb\u3002\u6211\u4eec\u901a\u8fc7 socket \u521b\u5efa\u7f51\u7edc\u6587\u4ef6\u65f6，Linux \u5185\u6838\u4f1a\u81ea\u52a8\u4e3a\u8fd9\u4e2a socket \u5206\u914d\u4e24\u5757\u4e13\u5c5e\u7f13\u51b2\u533a：\u5185\u6838\u63a5\u6536\u7f13\u51b2\u533a\u548c\u5185\u6838\u53d1\u9001\u7f13\u51b2\u533a，\u7528\u6765\u6682\u5b58\u7f51\u7edc\u6570\u636e\u5305\u3002\u5ba2\u6237\u7aef\u901a\u8fc7 sendto \u53d1\u6765\u7684\u6570\u636e，\u4f1a\u5148\u7ecf\u8fc7\u7f51\u5361，\u76f4\u63a5\u8fdb\u5165\u670d\u52a1\u7aef socket \u5bf9\u5e94\u7684\u5185\u6838\u63a5\u6536\u7f13\u51b2\u533a\u6392\u961f\u7f13\u5b58\u3002\u5f53\u670d\u52a1\u7aef\u8c03\u7528 recvfrom \u63a5\u6536\u6570\u636e\u65f6，\u672c\u8d28\u5c31\u662f\u64cd\u4f5c\u7cfb\u7edf\u628a\u5185\u6838\u7f13\u51b2\u533a\u91cc\u6682\u5b58\u597d\u7684\u6570\u636e，\u62f7\u8d1d\u5230\u6211\u4eec\u5728\u7528\u6237\u6808\u4e0a\u81ea\u5b9a\u4e49\u7684 inbuffer \u7f13\u51b2\u533a\u4e2d，\u4e4b\u540e\u6211\u4eec\u7684\u4e1a\u52a1\u4ee3\u7801\u624d\u80fd\u5bf9\u6570\u636e\u8fdb\u884c\u8bfb\u53d6\u3001\u6253\u5370\u548c\u5904\u7406\u4e8c\u8005\u5404\u53f8\u5176\u804c，\u6570\u636e\u662f\u4ece\u5185\u6838\u7f13\u51b2\u533a\u5230\u7528\u6237\u7f13\u51b2\u533a\u5355\u5411\u62f7\u8d1d\u7684\u5173\u7cfb，\u4e0d\u5b58\u5728\u4efb\u4f55\u77db\u76fe\u3002<\/p>\n

\u7b2c\u4e8c\u6b65\u5b9a\u4e49\u5ba2\u6237\u7aef\u5730\u5740\u7ed3\u6784\u4f53，\u8c03\u7528 recvfrom \u963b\u585e\u63a5\u6536\u6570\u636e :<\/p>\n

\"\"<\/p>\n

\u8fd9\u662f Start() \u51fd\u6570\u7684\u6838\u5fc3，\u6211\u4eec\u5c06\u8fd9\u4e00\u6b65\u518d\u62c6\u6210\u4e24\u90e8：peer \u7ed3\u6784\u4f53\u7684\u4f5c\u7528\u3001recvfrom \u7cfb\u7edf\u8c03\u7528\u5168\u89e3\u6790\u3002<\/p>\n

\u4e3a\u4ec0\u4e48\u8981\u5b9a\u4e49 struct sockaddr_in peer？<\/p>\n

\u6211\u4eec\u5728\u524d\u9762 Init() \u51fd\u6570\u91cc\u7684\u5b9a\u4e49\u7684 local \u7ed3\u6784\u4f53，\u5b58\u7684\u662f\u670d\u52a1\u7aef\u81ea\u5df1\u7684 IP + \u7aef\u53e3<\/span>；\u800c\u8fd9\u91cc\u7684 peer \u7ed3\u6784\u4f53，\u5219\u662f\u7528\u6765\u5b58\u653e\u5ba2\u6237\u7aef\u7684 IP + \u7aef\u53e3\u4fe1\u606f<\/span>\u3002\u56e0\u4e3a UDP \u662f\u65e0\u8fde\u63a5\u534f\u8bae，\u5ba2\u6237\u7aef\u6bcf\u6b21\u53d1\u6570\u636e\u90fd\u53ef\u80fd\u6765\u81ea\u4e0d\u540c\u7684\u5730\u5740；\u6240\u4ee5\u6211\u4eec\u5fc5\u987b\u901a\u8fc7 peer \u62ff\u5230\u5ba2\u6237\u7aef\u7684\u7f51\u7edc\u7aef\u70b9\u4fe1\u606f，\u624d\u80fd\u77e5\u9053 \u201c\u8c01\u5728\u7ed9\u6211\u53d1\u6d88\u606f\u201d，\u540e\u7eed\u624d\u80fd\u7cbe\u51c6\u628a\u56de\u58f0\u6570\u636e\u539f\u8def\u53d1\u56de\u53bb\u3002len = sizeof(peer) \u63d0\u524d\u8ba1\u7b97\u597d\u7ed3\u6784\u4f53\u5927\u5c0f，\u4f5c\u4e3a\u53c2\u6570\u4f20\u7ed9\u5185\u6838\u3002<\/p>\n

recvfrom \u7cfb\u7edf\u8c03\u7528<\/h4>\n

\"\"<\/p>\n

\"\" recvfrom \u662f UDP \u4e13\u7528\u7684\u63a5\u6536\u6570\u636e\u7cfb\u7edf\u8c03\u7528<\/span>，\u6838\u5fc3\u4f5c\u7528\u5c31\u662f\u963b\u585e\u7b49\u5f85\u5ba2\u6237\u7aef\u6570\u636e，\u540c\u65f6\u83b7\u53d6\u5ba2\u6237\u7aef\u7684\u7f51\u7edc\u5730\u5740<\/span>，6 \u4e2a\u53c2\u6570\u9010\u4e2a\u62c6\u89e3：<\/p>\n

  • \u7b2c\u4e00\u4e2a\u53c2\u6570 _sockfd \u662f\u6211\u4eec\u7b2c\u4e00\u6b65\u521b\u5efa\u7684 socket \u6587\u4ef6\u63cf\u8ff0\u7b26<\/span>，\u544a\u8bc9\u5185\u6838\u8981\u4ece\u8fd9\u4e2a\u7f51\u7edc\u6587\u4ef6\u00a0socket \u7684\u63a5\u6536\u7f13\u51b2\u533a\u91cc\u8bfb\u53d6\u6570\u636e；<\/li>\n
  • \u7b2c\u4e8c\u4e2a\u53c2\u6570 inbuffer \u662f\u6211\u4eec\u5b9a\u4e49\u7684\u7528\u6237\u6001\u63a5\u6536\u7f13\u51b2\u533a<\/span>，\u6570\u636e\u4ece\u5185\u6838\u7f13\u51b2\u533a\u62f7\u8d1d\u51fa\u6765\u540e，\u6700\u7ec8\u5b58\u5230\u8fd9\u4e2a\u6570\u7ec4\u91cc；<\/li>\n
  • \u7b2c\u4e09\u4e2a\u53c2\u6570 sizeof(inbuffer) – 1 \u662f\u6700\u5927\u8bfb\u53d6\u5b57\u8282\u6570<\/span>\u3002\u51cf 1 \u662f\u5b89\u5168\u89c4\u8303，\u9884\u7559 1 \u4e2a\u5b57\u8282\u4f4d\u7f6e\u7ed9\u5b57\u7b26\u4e32\u7ed3\u675f\u7b26 \\\\0，\u907f\u514d\u7f13\u51b2\u533a\u6ea2\u51fa；<\/li>\n
  • \u7b2c\u56db\u4e2a\u53c2\u6570 0 \u662f\u8bfb\u53d6\u6807\u5fd7\u4f4d，\u586b 0 \u4ee3\u8868\u9ed8\u8ba4\u963b\u585e\u6a21\u5f0f<\/span>\u2014\u2014 \u5982\u679c\u5185\u6838\u63a5\u6536\u7f13\u51b2\u533a\u91cc\u6ca1\u6709\u6570\u636e，\u7a0b\u5e8f\u4f1a\u5361\u5728\u8fd9\u4e00\u884c，\u4f11\u7720\u7b49\u5f85，\u76f4\u5230\u6709\u5ba2\u6237\u7aef\u53d1\u6570\u636e\u8fc7\u6765\u624d\u4f1a\u7ee7\u7eed\u6267\u884c；<\/li>\n
  • \u7b2c\u4e94\u4e2a\u53c2\u6570 (struct sockaddr *)&peer \u662f\u5ba2\u6237\u7aef\u5730\u5740\u8f93\u51fa\u53c2\u6570\u3002<\/span>\u5185\u6838\u6536\u5230\u6570\u636e\u540e，\u4f1a\u81ea\u52a8\u628a\u6570\u636e\u5305\u91cc\u5ba2\u6237\u7aef\u7684 IP + \u7aef\u53e3\u5730\u5740\u5199\u5165\u8fd9\u4e2a\u7ed3\u6784\u4f53，\u65b9\u4fbf\u540e\u7eed\u628a\u6570\u636e\u539f\u8def\u53d1\u56de\u53bb；<\/li>\n
  • \u7b2c\u516d\u4e2a\u53c2\u6570 &len \u662f\u5730\u5740\u957f\u5ea6\u8f93\u5165\u8f93\u51fa\u53c2\u6570<\/span>，\u4f20\u5165\u7ed3\u6784\u4f53\u5927\u5c0f，\u5185\u6838\u4f7f\u7528\u540e\u66f4\u65b0\u5b9e\u9645\u5199\u5165\u7684\u957f\u5ea6\u3002<\/li>\n

    \u8fd4\u56de\u503c n \u63a5\u6536\u6210\u529f\u65f6 n \u8868\u793a\u662f\u5b9e\u9645\u8bfb\u53d6\u5230\u7684\u5ba2\u6237\u7aef\u6570\u636e\u5b57\u8282\u6570；n < 0 \u8868\u793a\u5931\u8d25\u3002<\/p>\n

    \u7b2c\u4e09\u6b65\u89e3\u6790\u5ba2\u6237\u7aef\u5730\u5740 + \u5904\u7406\u4e1a\u52a1\u6570\u636e :<\/p>\n

    \"\"<\/p>\n

    \u9996\u5148\u6211\u4eec\u8981\u5c06\u7f51\u7edc\u5b57\u8282\u5e8f\u8f6c\u4e3b\u673a\u5b57\u8282\u5e8f，\u56e0\u4e3a\u5185\u6838\u4ece\u7f51\u7edc\u91cc\u62ff\u5230\u7684\u5ba2\u6237\u7aef IP\u3001\u7aef\u53e3，\u90fd\u662f\u7f51\u7edc\u5927\u7aef\u5e8f，CPU \u65e0\u6cd5\u76f4\u63a5\u8bc6\u522b，\u6240\u4ee5\u9700\u8981\u8f6c\u6362\u3002<\/p>\n

    \"\"ntohs() \u51fd\u6570\u8868\u793a network to host short，\u628a\u5ba2\u6237\u7aef\u7aef\u53e3\u4ece\u7f51\u7edc\u5927\u7aef\u5e8f，\u8f6c\u6210\u4e3b\u673a\u5c0f\u7aef\u5e8f，\u65b9\u4fbf\u6211\u4eec\u6253\u5370\u663e\u793a；<\/p>\n

    \"\"inet_ntoa() \u8868\u793a\u628a 32 \u4f4d\u4e8c\u8fdb\u5236 IP \u5730\u5740，\u8f6c\u6362\u6210\u6211\u4eec\u80fd\u770b\u61c2\u7684\u70b9\u5206\u5341\u8fdb\u5236\u5b57\u7b26\u4e32（\u5982 127.0.0.1\u3001192.168.x.x)\u3002<\/p>\n

    \"\"\u8fd9\u884c\u4ee3\u7801\u628a\u5ba2\u6237\u7aef\u7684 IP \u548c\u7aef\u53e3\u53f7，\u62fc\u63a5\u6210\u4e00\u4e2a\u6211\u4eec\u80fd\u76f4\u63a5\u770b\u61c2\u7684\u5b57\u7b26\u4e32\u683c\u5f0f，\u65b9\u4fbf\u65e5\u5fd7\u6253\u5370\u548c\u8c03\u8bd5\u3002client_ip \u5c31\u662f\u524d\u9762\u6211\u4eec\u7528 inet_ntoa(peer.sin_addr) \u8f6c\u6362\u5f97\u5230\u7684\u5b57\u7b26\u4e32 IP，\u6bd4\u5982 "127.0.0.1"\u3002std::to_string(client_port) \u628a ntohs \u8f6c\u6362\u540e\u7684\u7aef\u53e3\u53f7\u6574\u6570，\u6bd4\u5982 54321，\u8f6c\u6362\u6210\u5b57\u7b26\u4e32 "54321"\u3002\u6309\u7167\u62fc\u63a5\u683c\u5f0f：\u7528 [IP:\u7aef\u53e3] \u7684\u5f62\u5f0f，\u6bd4\u5982 [127.0.0.1:54321]，\u518d\u52a0\u4e0a # \u4f5c\u4e3a\u5206\u9694\u7b26，\u548c\u540e\u9762\u7684\u6d88\u606f\u4f53\u533a\u5206\u5f00\u3002\u8fd9\u4e48\u505a\u7684\u597d\u5904\u5c31\u662f\u65e5\u5fd7\u6253\u5370\u7684\u65f6\u5019，\u4e00\u773c\u5c31\u80fd\u770b\u51fa\u8fd9\u6761\u6d88\u606f\u6765\u81ea\u54ea\u4e2a\u5ba2\u6237\u7aef；<\/p>\n

    \"\"\u624b\u52a8\u8865\u5b57\u7b26\u4e32\u7ed3\u675f\u7b26\u3002\u56e0\u4e3a\u7f51\u7edc\u6570\u636e\u662f\u7eaf\u5b57\u8282\u6d41，\u6ca1\u6709\u7ed3\u675f\u6807\u8bb0，\u5fc5\u987b\u624b\u52a8\u52a0 \\\\0，\u5426\u5219\u6253\u5370\u5b57\u7b26\u4e32\u65f6\u4f1a\u51fa\u73b0\u4e71\u7801；<\/p>\n

    \"\" \u7b2c\u4e00\u884c\u4ee3\u7801\u662f\u628a\u6211\u4eec\u524d\u9762\u62fc\u63a5\u597d\u7684 client_address（\u4e5f\u5c31\u662f [\u5ba2\u6237\u7aefIP:\u7aef\u53e3]）\u548c\u6536\u5230\u7684\u539f\u59cb\u6d88\u606f inbuffer，\u4e00\u8d77\u6253\u5370\u5230\u65e5\u5fd7\u91cc\u3002\u540e\u4e24\u884c\u4ee3\u7801\u5148\u5b9a\u4e49\u4e00\u4e2a\u56fa\u5b9a\u524d\u7f00\u5b57\u7b26\u4e32 "server echo# "；\u628a\u5ba2\u6237\u7aef\u53d1\u6765\u7684 inbuffer \u5185\u5bb9\u62fc\u63a5\u5728\u540e\u9762；\u6700\u7ec8\u751f\u6210\u7684 echo_string \u5c31\u662f："server echo# "\u3002\u5b9e\u73b0\u6211\u4eec\u7684 \u201c\u56de\u58f0\u670d\u52a1\u5668\u201d \u529f\u80fd：\u5ba2\u6237\u7aef\u53d1\u4ec0\u4e48，\u670d\u52a1\u7aef\u539f\u6837\u8fd4\u56de，\u5e76\u4e14\u52a0\u4e0a\u670d\u52a1\u7aef\u7684\u6807\u8bb0\u524d\u7f00\u3002<\/p>\n

    \u6b65\u9aa4\u56db\u8c03\u7528 sendto \u539f\u8def\u56de\u590d\u6570\u636e\u7ed9\u5ba2\u6237\u7aef\u00a0 \"\"<\/p>\n

    sendto \u7cfb\u7edf\u8c03\u7528<\/h4>\n

    \"\" sendto \u662f UDP \u4e13\u7528\u7684\u53d1\u9001\u6570\u636e\u7cfb\u7edf\u8c03\u7528，\u6838\u5fc3\u4f5c\u7528\u662f\u628a\u5904\u7406\u597d\u7684\u56de\u58f0\u6570\u636e，\u539f\u8def\u53d1\u56de\u7ed9\u5bf9\u5e94\u7684\u5ba2\u6237\u7aef<\/span>，\u5b83\u4e5f\u662f 6 \u4e2a\u53c2\u6570，\u548c recvfrom() \u7684 6 \u4e2a\u53c2\u6570\u4e00\u4e00\u5bf9\u5e94，\u4f46\u662f\u903b\u8f91\u6070\u6070\u76f8\u53cd：<\/p>\n

  • \u7b2c\u4e00\u4e2a\u53c2\u6570 _sockfd \u540c\u6837\u4f7f\u7528\u6211\u4eec\u7684 socket \u6587\u4ef6\u63cf\u8ff0\u7b26<\/span>，\u901a\u8fc7\u5b83\u64cd\u4f5c\u5185\u6838\u7f51\u7edc\u6587\u4ef6 socket \u7684\u53d1\u9001\u7f13\u51b2\u533a；<\/li>\n
  • \u7b2c\u4e8c\u4e2a\u53c2\u6570 const void *buf \u662f\u8981\u53d1\u9001\u7684\u6570\u636e\u7684\u8d77\u59cb\u5730\u5740<\/span>，\u8fd9\u91cc\u6211\u4eec\u586b echo_string.c_str() \u8868\u793a\u628a C++ string \u8f6c\u6210 C \u8bed\u8a00 const char* \u683c\u5f0f，\u56e0\u4e3a echo_string \u5df2\u7ecf += \u4e86 inbuffer[]；<\/li>\n
  • \u7b2c\u4e09\u4e2a\u53c2\u6570 size_t len \u8868\u793a\u8981\u53d1\u9001\u7684\u6570\u636e\u5b9e\u9645\u5b57\u8282\u957f\u5ea6<\/span>；<\/li>\n
  • \u7b2c\u56db\u4e2a\u53c2\u6570 0 \u8868\u793a\u53d1\u9001\u6807\u5fd7\u4f4d，\u586b 0 \u4ee3\u8868\u9ed8\u8ba4\u6a21\u5f0f<\/span>；<\/li>\n
  • \u7b2c\u4e94\u4e2a\u53c2\u6570 (struct sockaddr *)&peer \u662f\u76ee\u6807\u5ba2\u6237\u7aef\u5730\u5740<\/span>\u3002\u8fd9\u5c31\u662f\u6211\u4eec\u524d\u9762\u89e3\u6790 peer \u7ed3\u6784\u4f53\u7684\u610f\u4e49 \u2014\u2014 \u544a\u8bc9\u5185\u6838，\u8fd9\u6761\u6570\u636e\u8981\u53d1\u7ed9\u54ea\u4e2a\u5ba2\u6237\u7aef\u7684 IP + \u7aef\u53e3；<\/li>\n
  • \u7b2c\u516d\u4e2a\u53c2\u6570 len \u662f\u5ba2\u6237\u7aef\u5730\u5740\u7ed3\u6784\u4f53\u7684\u957f\u5ea6<\/span>\u3002<\/li>\n

    recvfrom \u672c\u8d28\u662f：\u4ece socket \u5185\u6838\u63a5\u6536\u7f13\u51b2\u533a \u2192 \u62f7\u8d1d\u6570\u636e\u5230\u7528\u6237\u6001\u7f13\u51b2\u533a；<\/span><\/p>\n<\/p>\n

    sendto \u672c\u8d28\u662f：\u4ece\u7528\u6237\u6001\u7f13\u51b2\u533a \u2192 \u62f7\u8d1d\u6570\u636e\u5230 socket \u5185\u6838\u53d1\u9001\u7f13\u51b2\u533a \u2192 \u5185\u6838\u5f02\u6b65\u901a\u8fc7\u7f51\u5361\u53d1\u9001\u5230\u7f51\u7edc\u3002<\/span><\/p>\n

    EchoServerMain.cc \u670d\u52a1\u7aef\u5165\u53e3\u6587\u4ef6<\/h2>\n

    \u63a5\u4e0b\u6765\u5c31\u662f\u6211\u4eec UDP \u56de\u58f0\u670d\u52a1\u5668\u7684\u7a0b\u5e8f\u5165\u53e3\u6587\u4ef6，\u4e5f\u662f\u6574\u4e2a\u670d\u52a1\u7aef\u9879\u76ee\u7684\u5165\u53e3\u3002\u524d\u9762\u6211\u4eec\u62c6\u89e3\u4e86 UdpServer \u7c7b\u7684\u5934\u6587\u4ef6\u3001\u6210\u5458\u65b9\u6cd5\u3001\u5e95\u5c42\u901a\u4fe1\u903b\u8f91，\u800c\u8fd9\u4e2a\u5165\u53e3\u6587\u4ef6\u7684\u4f5c\u7528\u5c31\u662f\u6821\u9a8c\u542f\u52a8\u53c2\u6570\u3001\u521b\u5efa\u670d\u52a1\u7aef\u5bf9\u8c61\u3001\u8c03\u7528\u521d\u59cb\u5316\u4e0e\u4e1a\u52a1\u5faa\u73af，<\/span>\u4e00\u952e\u542f\u52a8\u6574\u4e2a UDP \u670d\u52a1\u3002\u6211\u4eec\u987a\u7740\u4ee3\u7801\u987a\u5e8f，\u5206 4 \u4e2a\u6b65\u9aa4\u9010\u884c\u62c6\u89e3，\u540c\u65f6\u8bb2\u6e05\u5b83\u548c\u5ba2\u6237\u7aef\u7684\u5173\u8054\u5173\u7cfb\u3002<\/p>\n

    \"\"<\/p>\n

    \u7b2c\u4e00\u6b65\u662f\u5de5\u5177\u51fd\u6570\u5b9a\u4e49 \u2014\u2014 \u7a0b\u5e8f\u4f7f\u7528\u63d0\u793a:<\/p>\n

    \"\" Usage \u662f\u4e00\u4e2a\u9759\u6001\u5de5\u5177\u51fd\u6570，\u4e13\u95e8\u7528\u6765\u6253\u5370\u7a0b\u5e8f\u7684\u6b63\u786e\u542f\u52a8\u683c\u5f0f\u3002\u53c2\u6570 process \u7528\u6765\u63a5\u6536\u7a0b\u5e8f\u81ea\u8eab\u540d\u79f0（\u6bd4\u5982 .\/server_udp)；<\/p>\n<\/p>\n

    \u8f93\u51fa\u683c\u5f0f\u4e3a .\/server_udp + local_port<\/span>，\u4e5f\u5c31\u662f\u544a\u8bc9\u4f7f\u7528\u8005：\u5728 .\/server_udp \u542f\u52a8\u670d\u52a1\u65f6，\u4e5f\u5fc5\u987b\u5728\u540e\u9762\u4f20\u5165\u4e00\u4e2a\u7aef\u53e3\u53f7\u53c2\u6570 port；\u5426\u5219\u53c2\u6570\u6570\u91cf\u5c31\u4e0d\u5bf9，\u4f1a\u81ea\u52a8\u89e6\u53d1\u63d0\u793a\u3002<\/p>\n

    \u7b2c\u4e8c\u90e8\u5c31\u662f\u4e3b\u51fd\u6570\u7684\u5165\u53e3 :<\/p>\n

    \"\" argc \u662f\u547d\u4ee4\u884c\u53c2\u6570\u4e2a\u6570，\u7a0b\u5e8f\u81ea\u8eab\u540d\u79f0\u7b97\u7b2c 1 \u4e2a\u53c2\u6570；argv[] \u662f\u547d\u4ee4\u884c\u53c2\u6570\u6570\u7ec4，argv[0] \u5b58\u7a0b\u5e8f\u540d，argv[1] \u5b58\u7528\u6237\u4f20\u5165\u7684\u7aef\u53e3\u53f7\u3002 \u6211\u4eec\u7684\u670d\u52a1\u7aef\u542f\u52a8\u540e，\u5fc5\u987b\u4f20\u5165 1 \u4e2a\u7aef\u53e3\u53c2\u6570，\u6240\u4ee5\u8981\u6c42 argc == 2；\u5982\u679c\u53c2\u6570\u6570\u91cf\u4e0d\u5bf9\u5c31\u4f1a\u8c03\u7528 Usage \u6253\u5370\u4f7f\u7528\u63d0\u793a，\u76f4\u63a5\u4ee5 USAGE_ERR \u9519\u8bef\u7801\u9000\u51fa\u7a0b\u5e8f；\u8fd9\u4e00\u6b65\u662f\u7a0b\u5e8f\u542f\u52a8\u7684\u5b89\u5168\u6821\u9a8c，\u907f\u514d\u540e\u7eed\u56e0\u4e3a\u7aef\u53e3\u53c2\u6570\u7f3a\u5931\u5bfc\u81f4\u521d\u59cb\u5316\u5931\u8d25\u3002<\/p>\n

    \u7b2c\u4e09\u6b65\u5c31\u662f\u73af\u5883\u914d\u7f6e + \u7aef\u53e3\u53c2\u6570\u89e3\u6790 :<\/p>\n

    \"\" ENABLE_CONSOLE_LOG_STRATEGY() \u662f\u542f\u7528\u63a7\u5236\u53f0\u65e5\u5fd7\u8f93\u51fa\u3002<\/p>\n<\/p>\n

    argv[1] \u662f\u7528\u6237\u547d\u4ee4\u884c\u4f20\u5165\u7684\u7aef\u53e3\u5b57\u7b26\u4e32（\u6bd4\u5982 8080)；std::stoi(argv[1]) \u8868\u793a\u5c06\u5b57\u7b26\u4e32\u7aef\u53e3 argv[1]\u00a0\u8f6c\u4e3a\u6574\u6570，\u8d4b\u503c\u7ed9 uint16_t \u7c7b\u578b\u7684 server_port<\/span>；\u8fd9\u91cc\u7684\u7aef\u53e3，\u5c31\u662f\u670d\u52a1\u7aef\u5bf9\u5916\u63d0\u4f9b\u670d\u52a1\u7684\u552f\u4e00\u6807\u8bc6，\u540e\u7eed\u5ba2\u6237\u7aef\u5fc5\u987b\u6307\u5b9a\u8fd9\u4e2a\u7aef\u53e3，\u624d\u80fd\u548c\u670d\u52a1\u7aef\u5efa\u7acb UDP \u901a\u4fe1\u3002<\/p>\n

    \u6700\u540e\u4e00\u6b65\u521b\u5efa\u670d\u52a1\u7aef\u5bf9\u8c61 + \u542f\u52a8\u670d\u52a1\u95ed\u73af:<\/p>\n

    \"\" \u9996\u5148\u6211\u4eec\u521b\u5efa\u667a\u80fd\u6307\u9488\u5bf9\u8c61，\u91c7\u7528 C++14 \u667a\u80fd\u6307\u9488\u7ba1\u7406 UdpServer \u5bf9\u8c61，\u81ea\u52a8\u7ba1\u7406\u5185\u5b58，\u7a0b\u5e8f\u9000\u51fa\u65f6\u81ea\u52a8\u6790\u6784，\u907f\u514d\u5185\u5b58\u6cc4\u6f0f；\u521b\u5efa\u5bf9\u8c61\u65f6，\u4f20\u5165\u6211\u4eec\u89e3\u6790\u597d\u7684 server_port \u7aef\u53e3\u53f7，\u7aef\u53e3\u4fe1\u606f\u76f4\u63a5\u4f20\u5165\u670d\u52a1\u7aef\u7c7b，\u548c\u524d\u9762\u5934\u6587\u4ef6\u7684\u6784\u9020\u51fd\u6570\u5f62\u6210\u95ed\u73af\u3002<\/span><\/p>\n<\/p>\n

    \u968f\u540e\u8c03\u7528 Init () \u521d\u59cb\u5316，\u8c03\u7528\u6211\u4eec\u4e4b\u524d\u8be6\u7ec6\u62c6\u89e3\u7684\u521d\u59cb\u5316\u51fd\u6570：\u521b\u5efa socket \u5185\u6838\u6587\u4ef6\u3001\u7ed1\u5b9a INADDR_ANY \u5168\u7f51\u5361\u76d1\u542c\u3001\u5b8c\u6210\u64cd\u4f5c\u7cfb\u7edf\u7aef\u53e3\u6ce8\u518c；\u6267\u884c\u5b8c\u8fd9\u4e00\u6b65：\u670d\u52a1\u7aef\u5df2\u7ecf\u5728\u64cd\u4f5c\u7cfb\u7edf\u4e2d\u6ce8\u518c\u5b8c\u6210，\u7aef\u53e3\u5904\u4e8e\u76d1\u542c\u72b6\u6001，\u5ba2\u6237\u7aef\u6b64\u65f6\u5df2\u7ecf\u53ef\u4ee5\u53d1\u8d77\u8fde\u63a5\u8bf7\u6c42\u3002<\/p>\n<\/p>\n

    \u6700\u540e\u8c03\u7528 Start () \u542f\u52a8\u4e1a\u52a1\u5faa\u73af，\u8c03\u7528\u6211\u4eec\u7684\u6838\u5fc3\u4e1a\u52a1\u51fd\u6570：\u5f00\u542f\u6b7b\u5faa\u73af，\u963b\u585e\u7b49\u5f85\u5ba2\u6237\u7aef\u6570\u636e\u3001\u63a5\u6536\u89e3\u6790\u5ba2\u6237\u7aef\u5730\u5740\u3001\u5c01\u88c5\u56de\u58f0\u6570\u636e\u3001sendto \u539f\u8def\u56de\u590d；\u6267\u884c\u5b8c\u8fd9\u4e00\u6b65：\u670d\u52a1\u7aef\u8fdb\u5165\u670d\u52a1\u72b6\u6001，\u6301\u7eed\u5904\u7406\u6240\u6709\u5ba2\u6237\u7aef\u7684 UDP \u8bf7\u6c42，\u76f4\u5230\u7a0b\u5e8f\u624b\u52a8\u7ec8\u6b62\u3002<\/p>\n

    \u8fd0\u884c\u670d\u52a1\u7aef :<\/h4>\n

    \u5230\u76ee\u524d\u4e3a\u6b62，\u6211\u4eec\u5bf9\u6574\u4e2a\u670d\u52a1\u7aef\u7684\u4ee3\u7801\u7f16\u5199\u5c31\u5b8c\u6210\u4e86，\u4e0b\u6765\u6211\u4eec\u53ef\u4ee5\u8fd0\u884c\u4e00\u4e0b\u670d\u52a1\u7aef\u7684\u7a0b\u5e8f :\u00a0<\/p>\n

    \"\"\u5f53\u6211\u4eec\u6267\u884c\u547d\u4ee4 .\/server_udp 8080 \u540e，\u7ec8\u7aef\u5c31\u8f93\u51fa\u4e86\u4e24\u884c\u65e5\u5fd7 :\u00a0<\/p>\n<\/p>\n

    \"\"\u7b2c\u4e00\u884c\u65e5\u5fd7\u5bf9\u5e94 socket() \u8c03\u7528\u6210\u529f，sockfd: 3 \u8bf4\u660e\u5185\u6838\u6210\u529f\u4e3a\u6211\u4eec\u521b\u5efa\u4e86 socket \u6587\u4ef6\u5bf9\u8c61，\u5e76\u5206\u914d\u4e86\u6587\u4ef6\u63cf\u8ff0\u7b26 3\u3002<\/p>\n<\/p>\n

    \"\"\u7b2c\u4e8c\u884c\u65e5\u5fd7\u5bf9\u5e94 bind() \u8c03\u7528\u6210\u529f，port: 8080 \u8bf4\u660e\u6211\u4eec\u7ed1\u5b9a\u7684 8080 \u7aef\u53e3\u6ce8\u518c\u6210\u529f\u3002\u7ed3\u5408\u6211\u4eec\u4f7f\u7528\u7684 INADDR_ANY，\u670d\u52a1\u7aef\u5df2\u7ecf\u5f00\u59cb\u76d1\u542c\u672c\u673a\u6240\u6709\u7f51\u5361\u4e0a\u3001\u76ee\u6807\u7aef\u53e3\u4e3a 8080 \u7684 UDP \u6570\u636e\u5305\u3002<\/p>\n<\/p>\n

    \u8f93\u51fa\u5b8c\u8fd9\u4e24\u884c\u65e5\u5fd7\u540e，\u5149\u6807\u505c\u7559\u5728\u4e0b\u4e00\u884c，\u7a0b\u5e8f\u6ca1\u6709\u9000\u51fa，\u4e5f\u6ca1\u6709\u65b0\u65e5\u5fd7\u8f93\u51fa，\u8fd9\u6b63\u662f\u6211\u4eec\u671f\u671b\u7684\u72b6\u6001：\u670d\u52a1\u7aef\u5df2\u7ecf\u6210\u529f\u521b\u5efa socket\u3001\u7ed1\u5b9a\u7aef\u53e3，\u8fdb\u5165\u4e86 Start() \u51fd\u6570\u91cc\u7684 while(true) \u6b7b\u5faa\u73af\u3002\u6b64\u65f6 recvfrom() \u6b63\u5728\u5185\u6838\u4e2d\u963b\u585e\u7b49\u5f85，\u670d\u52a1\u7aef\u5df2\u7ecf\u51c6\u5907\u597d\u63a5\u6536\u4efb\u4f55\u5ba2\u6237\u7aef\u53d1\u6765\u7684\u6d88\u606f\u3002<\/p>\n

    EchoClient.cc \u5ba2\u6237\u7aef\u6587\u4ef6 :<\/h2>\n

    \u524d\u9762\u6211\u4eec\u5b8c\u6574\u62c6\u89e3\u4e86 UDP \u670d\u52a1\u7aef\u7684\u5168\u94fe\u8def\u903b\u8f91，\u670d\u52a1\u7aef\u662f\u88ab\u52a8\u76d1\u542c\u3001\u7b49\u5f85\u5ba2\u6237\u7aef\u8fde\u63a5\u7684\u89d2\u8272；\u800c\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u7aef\u6b63\u597d\u76f8\u53cd，\u662f\u4e3b\u52a8\u53d1\u8d77\u901a\u4fe1\u3001\u5b9a\u5411\u7ed9\u6307\u5b9a\u670d\u52a1\u7aef\u53d1\u6570\u636e\u7684\u89d2\u8272\u3002\u4e0b\u9762\u6211\u4eec\u5c31\u6765\u770b\u770b\u5ba2\u6237\u7aef\u7684\u4ee3\u7801:<\/p>\n

    \u5ba2\u6237\u7aef\u4e0e\u670d\u52a1\u7aef\u7684\u6838\u5fc3\u5f02\u540c<\/h3>\n

    \u2705 \u76f8\u540c\u70b9 :\u00a0\u5ba2\u6237\u7aef\u4e0e\u670d\u52a1\u7aef\u7684\u4ee3\u7801\u6838\u5fc3\u5b8c\u5168\u4e00\u81f4，\u901a\u4fe1\u63a5\u53e3\u5b8c\u5168\u4e00\u81f4<\/p>\n

    1. \u90fd\u9700\u8981\u901a\u8fc7 socket() \u521b\u5efa\u5185\u6838\u7f51\u7edc\u6587\u4ef6\u3001\u83b7\u53d6 fd \u6587\u4ef6\u63cf\u8ff0\u7b26，\u4f9d\u8d56 Linux \u5185\u6838\u7f13\u51b2\u533a\u5b8c\u6210\u6570\u636e\u6536\u53d1；<\/span><\/p>\n<\/p>\n

    2. \u90fd\u4f7f\u7528sendto()\u53d1\u9001\u6570\u636e\u3001recvfrom()\u63a5\u6536\u6570\u636e<\/span>，\u9075\u5faa UDP \u65e0\u8fde\u63a5\u901a\u4fe1\u6807\u51c6\u3002<\/p>\n

    \u274c \u6838\u5fc3\u4e0d\u540c\u70b9（\u6700\u5173\u952e）<\/p>\n

    \u89d2\u8272\u5b9a\u4f4d\u4e0d\u540c :<\/p>\n

    \u00a0 1. \u670d\u52a1\u7aef\u662f\u88ab\u52a8\u65b9，\u5fc5\u987bbind()\u7ed1\u5b9a\u56fa\u5b9a\u7aef\u53e3 + INADDR_ANY\u5168\u7f51\u5361\u76d1\u542c，\u8ba9\u5ba2\u6237\u7aef\u80fd\u7cbe\u51c6\u627e\u5230\u81ea\u5df1；<\/p>\n

    \u00a0 2. \u800c\u5ba2\u6237\u7aef\u662f\u4e3b\u52a8\u65b9，\u4e0d\u9700\u8981\u624b\u52a8 bind \u7ed1\u5b9a\u7aef\u53e3<\/span>，\u9996\u6b21\u8c03\u7528 sendto() \u65f6，\u64cd\u4f5c\u7cfb\u7edf\u4f1a\u81ea\u52a8\u5206\u914d\u968f\u673a\u4e34\u65f6\u7aef\u53e3，\u7531 OS \u7ba1\u7406\u7aef\u53e3\u552f\u4e00\u6027，\u907f\u514d\u7aef\u53e3\u51b2\u7a81\u3002<\/p>\n

    \u5730\u5740\u903b\u8f91\u4e0d\u540c :<\/p>\n

    \u00a0 1. \u670d\u52a1\u7aef\u9700\u8981\u7ed1\u5b9a\u81ea\u5df1\u7684\u5730\u5740，\u7b49\u5f85\u6240\u6709\u5ba2\u6237\u7aef\u4e3b\u52a8\u627e\u8fc7\u6765；<\/p>\n

    \u00a0 2. \u800c\u5ba2\u6237\u7aef\u9700\u8981\u9884\u5148\u914d\u7f6e\u670d\u52a1\u7aef\u7684 IP + \u7aef\u53e3，\u4e3b\u52a8\u5b9a\u5411\u8bbf\u95ee\u6307\u5b9a\u670d\u52a1\u7aef\u3002<\/p>\n

    \u5faa\u73af\u903b\u8f91\u4e0d\u540c :<\/p>\n

    \u00a0 1. \u670d\u52a1\u7aef\u662f\u6b7b\u5faa\u73afwhile(true)\u963b\u585e\u76d1\u542c，\u6301\u7eed\u7b49\u5f85\u4efb\u610f\u5ba2\u6237\u7aef\u8bf7\u6c42；<\/p>\n

    \u00a0 2. \u5ba2\u6237\u7aef\u662f\u6b7b\u5faa\u73af\u7528\u4e8e\u6301\u7eed\u83b7\u53d6\u7528\u6237\u8f93\u5165\u3001\u4e3b\u52a8\u53d1\u8d77\u5355\u6b21\u901a\u4fe1，\u6bcf\u6b21\u5faa\u73af\u5b8c\u6210\u4e00\u6b21 \u201c\u53d1\u9001 – \u63a5\u6536\u201d \u7684\u8bf7\u6c42\u5e94\u7b54\u3002<\/p>\n

    \u5ba2\u6237\u7aef\u7684\u6267\u884c\u903b\u8f91\u53ef\u4ee5\u5206\u4e3a 5 \u4e2a\u6838\u5fc3\u6b65\u9aa4，\u4e0b\u9762\u6211\u4eec\u9010\u4e00\u4ecb\u7ecd：<\/p>\n

    1. \u5934\u6587\u4ef6\u4e0e\u4f7f\u7528\u63d0\u793a\u51fd\u6570<\/h3>\n

    \"\"<\/p>\n

    1. \u5934\u6587\u4ef6\u548c\u670d\u52a1\u7aef\u5b8c\u5168\u4e00\u81f4，\u5305\u542b\u7f51\u7edc\u7f16\u7a0b\u5fc5\u5907\u7684 socket.h\u3001inet.h\u3001in.h<\/span>，\u63d0\u4f9b socket \u521b\u5efa\u3001IP \/ \u7aef\u53e3\u8f6c\u6362\u3001\u5730\u5740\u7ed3\u6784\u4f53\u5b9a\u4e49\u7684\u7cfb\u7edf\u63a5\u53e3；<\/p>\n<\/p>\n

    2. Usage \u5de5\u5177\u51fd\u6570：\u6253\u5370\u5ba2\u6237\u7aef\u6b63\u786e\u542f\u52a8\u683c\u5f0f\u3002\u5ba2\u6237\u7aef\u542f\u52a8\u5fc5\u987b\u4f20\u5165\u4e24\u4e2a\u53c2\u6570：<\/span>\u670d\u52a1\u7aef IP\u3001\u670d\u52a1\u7aef\u7aef\u53e3<\/span>，\u4f8b\u5982 .\/client_udp 127.0.0.1 8080<\/span>\u3002\u53c2\u6570\u7f3a\u5931\u4f1a\u76f4\u63a5\u63d0\u793a\u7528\u6cd5\u5e76\u9000\u51fa，\u548c\u670d\u52a1\u7aef\u53c2\u6570\u6821\u9a8c\u903b\u8f91\u5bf9\u5e94，\u4f46\u6821\u9a8c\u7684\u53c2\u6570\u542b\u4e49\u5b8c\u5168\u4e0d\u540c\u3002<\/p>\n

    2. \u4e3b\u51fd\u6570\u5165\u53e3 & \u542f\u52a8\u53c2\u6570<\/h3>\n

    \"\"<\/p>\n

  • argv[0] \u8868\u793a\u5ba2\u6237\u7aef\u7a0b\u5e8f\u540d；<\/li>\n
  • argv[1] \u8868\u793a\u670d\u52a1\u7aef IP（\u5982127.0.0.1\u3001\u516c\u7f51 IP)；<\/li>\n
  • argv[2] \u8868\u793a\u670d\u52a1\u7aef\u7aef\u53e3（\u5fc5\u987b\u548c\u670d\u52a1\u7aef bind \u7ed1\u5b9a\u7684\u7aef\u53e3\u5b8c\u5168\u4e00\u81f4，\u5982 8080)；<\/li>\n

    1. \u5f53 argc != 3 \u5c31\u4f1a\u76f4\u63a5\u9000\u51fa，\u56e0\u4e3a\u5ba2\u6237\u7aef\u5fc5\u987b\u660e\u786e\u77e5\u9053\u670d\u52a1\u7aef\u7684 IP \u548c\u7aef\u53e3，\u8fd9\u662f\u4e3b\u52a8\u901a\u4fe1\u7684\u524d\u63d0；<\/p>\n<\/p>\n

    2. \u4e0b\u6765\u5c31\u5c06\u547d\u4ee4\u884c\u4f20\u5165\u7684\u5b57\u7b26\u4e32 IP\u3001\u7aef\u53e3，\u8f6c\u4e3a\u7a0b\u5e8f\u53ef\u7528\u7684 std::string \u548c uint16_t \u7c7b\u578b，\u4e3a\u540e\u7eed\u505a\u51c6\u5907\u3002<\/p>\n

    \u4e3a\u4ec0\u4e48\u5ba2\u6237\u7aef\u4f20\u5165\u7684\u662f\u670d\u52a1\u7aef\u7684 IP \u548c\u670d\u52a1\u7aef\u7684\u7aef\u53e3\u53f7？<\/p>\n<\/p>\n

    \u56e0\u4e3a\u5ba2\u6237\u7aef\u662f\u4e3b\u52a8\u627e\u4eba\u7684\u4e00\u65b9，\u5b83\u5fc5\u987b\u77e5\u9053\u5bf9\u65b9\u5728\u54ea，\u4e0d\u7136\u4e0d\u77e5\u9053\u6570\u636e\u8be5\u53d1\u7ed9\u8c01\u3002\u5ba2\u6237\u7aef\u542f\u52a8\u4f20\u5165\u670d\u52a1\u7aef IP \u548c\u7aef\u53e3，\u672c\u8d28\u662f\u4e3a\u4e86\u7ed9\u64cd\u4f5c\u7cfb\u7edf\u6307\u660e\u901a\u4fe1\u76ee\u6807\u3002UDP \u662f\u65e0\u8fde\u63a5\u901a\u4fe1，\u5ba2\u6237\u7aef\u6bcf\u6b21\u53d1\u9001\u6570\u636e\u5305\u90fd\u5fc5\u987b\u660e\u786e\u6307\u5b9a\u63a5\u6536\u65b9\u5730\u5740，\u56e0\u6b64\u5fc5\u987b\u9884\u5148\u77e5\u9053\u670d\u52a1\u7aef\u56fa\u5b9a\u7684\u76d1\u542c IP \u4e0e\u7aef\u53e3；\u800c\u5ba2\u6237\u7aef\u81ea\u8eab\u7684\u5730\u5740\u7531\u64cd\u4f5c\u7cfb\u7edf\u81ea\u52a8\u5206\u914d\u968f\u673a\u4e34\u65f6\u7aef\u53e3，\u65e0\u9700\u624b\u52a8\u914d\u7f6e\u3002<\/p>\n

    3. \u521b\u5efa socket<\/h3>\n

    \"\"<\/p>\n

    1. \u5ba2\u6237\u7aef\u521b\u5efa socket \u903b\u8f91\u548c\u670d\u52a1\u7aef\u4e00\u81f4：AF_INET \u8868\u793a IPv4 \u534f\u8bae；SOCK_DGRAM \u8868\u793a UDP \u65e0\u8fde\u63a5\u6570\u636e\u62a5；\u6838\u5fc3\u4f5c\u7528\u5c31\u662f\u5ba2\u6237\u7aef\u540c\u6837\u5411 Linux \u5185\u6838\u7533\u8bf7\u521b\u5efa\u4e00\u4e2a socket \u7f51\u7edc\u6587\u4ef6，\u62ff\u5230\u552f\u4e00 fd\u3002\u540e\u7eed\u6240\u6709\u7684\u64cd\u4f5c，\u90fd\u901a\u8fc7\u8fd9\u4e2a fd \u64cd\u4f5c\u5ba2\u6237\u7aef socket \u7684\u5185\u6838\u6536\u53d1\u7f13\u51b2\u533a\u3002<\/p>\n<\/p>\n

    2. \u9700\u8981\u6ce8\u610f\u7684\u662f : \u670d\u52a1\u7aef\u548c\u5ba2\u6237\u7aef\u7528\u7684\u4e0d\u662f\u540c\u4e00\u4e2a\u00a0socket，\u4e8c\u8005\u5b8c\u5168\u72ec\u7acb\u3002\u670d\u52a1\u7aef\u8c03\u7528 socket () \u521b\u5efa\u4e00\u4e2a\u5185\u6838\u7f51\u7edc\u6587\u4ef6，\u7ed1\u5b9a\u56fa\u5b9a\u7aef\u53e3\u88ab\u52a8\u76d1\u542c；\u5ba2\u6237\u7aef\u540c\u6837\u8c03\u7528 socket () \u521b\u5efa\u53e6\u4e00\u4e2a\u5168\u65b0\u7684\u5185\u6838\u7f51\u7edc\u6587\u4ef6，\u7531\u64cd\u4f5c\u7cfb\u7edf\u5206\u914d\u968f\u673a\u7aef\u53e3\u4e3b\u52a8\u901a\u4fe1\u3002\u4e8c\u8005\u662f\u64cd\u4f5c\u7cfb\u7edf\u4e2d\u4e24\u4e2a\u5b8c\u5168\u72ec\u7acb\u7684\u6587\u4ef6\u5bf9\u8c61，\u53ea\u662f\u4f9d\u9760\u300cIP + \u7aef\u53e3\u300d\u7684\u5bfb\u5740\u89c4\u5219\u901a\u8fc7\u7f51\u7edc\u4ea4\u6362\u6570\u636e，\u4e0d\u5b58\u5728\u4efb\u4f55\u5171\u7528\u5173\u7cfb\u3002<\/span><\/p>\n

    3. \u5e76\u4e14\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u7aef\u5173\u952e\u533a\u522b：\u5ba2\u6237\u7aef\u521b\u5efa socket \u540e，\u4e0d\u6267\u884c bind \u7ed1\u5b9a\u3002<\/span>\u4e3a\u4ec0\u4e48?<\/span><\/p>\n

    \u56e0\u4e3a bind \u7684\u672c\u8d28\u76f8\u5f53\u4e8e\u4e3b\u52a8\u544a\u8bc9\u64cd\u4f5c\u7cfb\u7edf：\u6211\u8981\u5360\u7528\u8fd9\u4e2a IP + \u7aef\u53e3，\u522b\u4eba\u90fd\u4e0d\u80fd\u7528\u3002\u6240\u4ee5\u670d\u52a1\u7aef\u5fc5\u987b bind：\u56e0\u4e3a\u5b83\u8981\u5f53\u56fa\u5b9a\u670d\u52a1\u70b9，\u5fc5\u987b\u63d0\u524d\u5360\u597d\u4e00\u4e2a\u56fa\u5b9a\u7aef\u53e3，\u8ba9\u6240\u6709\u4eba\u90fd\u80fd\u627e\u5230\u5b83；\u800c\u5ba2\u6237\u7aef\u5219\u4e0d\u9700\u8981\u7528 bind，\u56e0\u4e3a\u5ba2\u6237\u7aef\u53ea\u662f\u4e34\u65f6\u8bbf\u95ee\u8005，\u4e0d\u9700\u8981\u56fa\u5b9a\u8eab\u4efd，\u64cd\u4f5c\u7cfb\u7edf\u4f1a\u5728\u5e95\u5c42\u968f\u673a\u6311\u4e00\u4e2a\u968f\u673a\u7684\u7a7a\u95f2\u7aef\u53e3；\u81ea\u52a8\u628a\u5ba2\u6237\u7aef\u672c\u673a IP + \u8fd9\u4e2a\u968f\u673a\u7aef\u53e3\u7ed1\u5b9a\u7ed9\u5ba2\u6237\u7aef\u7684 socket；\u540e\u7eed\u6240\u6709\u6536\u53d1\u6570\u636e，\u90fd\u7528\u8fd9\u4e2a\u81ea\u52a8\u5206\u914d\u7684\u4e34\u65f6\u7aef\u53e3\u3002<\/p>\n<\/p>\n

    \u8fd9\u5c31\u76f8\u5f53\u4e8e\u6211\u4eec\u5237\u6296\u97f3，\u6296\u97f3\u670d\u52a1\u5668（\u670d\u52a1\u7aef）\u5fc5\u987b bind\u3002\u56e0\u4e3a\u6296\u97f3\u8981\u7ed9\u5168\u56fd\u51e0\u4ebf\u7528\u6237\u63d0\u4f9b\u670d\u52a1，\u5b83\u5fc5\u987b\u56fa\u5b9a\u4e00\u4e2a\u4e0d\u53d8 IP + \u7aef\u53e3\u3002\u7528\u6765\u63a5\u6536\u6240\u6709\u7528\u6237\u7684\u89c6\u9891\u8bf7\u6c42\u3002\u800c\u6211\u4eec\u7684\u624b\u673a(\u5ba2\u6237\u7aef)\u4e0d\u7528 bind\u3002\u5f53\u6211\u4eec\u5237\u6296\u97f3\u65f6，\u53ea\u9700\u8981\u6253\u5f00 APP，\u64cd\u4f5c\u7cfb\u7edf\u4f1a\u81ea\u52a8\u7ed9\u624b\u673a\u5206\u914d\u4e00\u4e2a\u4e34\u65f6\u7aef\u53e3，\u7528\u5b8c\u5c31\u56de\u6536\u3002<\/p>\n

    4. \u6784\u5efa\u670d\u52a1\u7aef socket \u76ee\u6807\u5730\u5740<\/h3>\n

    \"\" struct sockaddr_in server \u7528\u6765\u5b58\u653e\u670d\u52a1\u7aef\u7684 IP + \u7aef\u53e3<\/span>，\u4f5c\u4e3a\u5ba2\u6237\u7aef\u53d1\u9001\u6570\u636e\u7684\u76ee\u6807\u5730\u5740；\u670d\u52a1\u7aef\u6784\u5efa\u7684\u662f\u81ea\u5df1\u7684\u76d1\u542c\u5730\u5740；\u5ba2\u6237\u7aef\u6784\u5efa\u7684\u662f\u5bf9\u65b9\u7684\u76ee\u6807\u5730\u5740；<\/p>\n<\/p>\n

    \"\" \u6e05\u7a7a\u5730\u5740\u7ed3\u6784\u4f53\u810f\u6570\u636e，\u548c\u670d\u52a1\u7aef\u89c4\u8303\u4e00\u81f4；<\/p>\n

    \"\" \u4fdd\u6301 IPv4 \u534f\u8bae\u4e00\u81f4；<\/p>\n

    \"\" \u7aef\u53e3\u4e3b\u673a\u5e8f\u8f6c\u7f51\u7edc\u5e8f，\u5fc5\u987b\u548c\u670d\u52a1\u7aef\u7aef\u53e3\u5b8c\u5168\u4e00\u81f4；<\/p>\n

    \"\" \u5c06\u5341\u8fdb\u5236\u7684 IP（\u5982 127.0.0.1)，\u8f6c\u4e3a 32 \u4f4d\u7f51\u7edc\u4e8c\u8fdb\u5236 IP，\u7528\u4e8e\u7f51\u7edc\u4f20\u8f93\u5bfb\u5740；<\/p>\n<\/p>\n

    \u5ba2\u6237\u7aef\u540e\u7eed\u6bcf\u6b21 sendto \u53d1\u9001\u6570\u636e，\u90fd\u4f1a\u6307\u5b9a\u8fd9\u4e2a server \u7ed3\u6784\u4f53，\u544a\u8bc9\u64cd\u4f5c\u7cfb\u7edf：\u8fd9\u6761 UDP \u6570\u636e\u5305，\u8981\u53d1\u5f80\u8fd9\u4e2a IP + \u7aef\u53e3\u7684\u670d\u52a1\u7aef\u3002<\/p>\n

    5. \u5faa\u73af\u4ea4\u4e92\u903b\u8f91<\/h3>\n

    \"\"<\/p>\n

    (1). \u83b7\u53d6\u7528\u6237\u8f93\u5165<\/p>\n

    \"\" \u6bcf\u6b21\u5faa\u73af\u4e3b\u52a8\u83b7\u53d6\u7528\u6237\u8f93\u5165\u7684\u5b57\u7b26\u4e32，\u4f5c\u4e3a\u8981\u53d1\u9001\u7ed9\u670d\u52a1\u7aef\u7684\u6570\u636e\u3002<\/p>\n

    (2). sendto \u4e3b\u52a8\u53d1\u9001\u6570\u636e<\/p>\n

    \"\"<\/p>\n

      \n
    • sockfd \u662f\u5ba2\u6237\u7aef\u81ea\u5df1\u7684 socket fd；<\/li>\n
    • message.c_str() \u662f\u8981\u53d1\u9001\u7684\u7528\u6237\u6570\u636e；<\/li>\n
    • (struct sockaddr*)&server \u662f\u76ee\u6807\u670d\u52a1\u7aef\u5730\u5740（\u6211\u4eec\u524d\u9762\u63d0\u524d\u6784\u5efa\u597d\u7684 IP + \u7aef\u53e3）；<\/li>\n<\/ul>\n

      \u5ba2\u6237\u7aef\u6ca1\u6709\u624b\u52a8\u8c03\u7528 bind()，\u9996\u6b21\u8c03\u7528 sendto() \u65f6，Linux \u64cd\u4f5c\u7cfb\u7edf\u4f1a\u81ea\u52a8\u4e3a\u5ba2\u6237\u7aef socket \u5206\u914d\u4e00\u4e2a\u968f\u673a\u4e34\u65f6\u7aef\u53e3；<\/span>\u5b8c\u6210\u5ba2\u6237\u7aef fd\u3001\u968f\u673a\u7aef\u53e3\u3001\u672c\u673a IP \u7684\u5185\u6838\u7ed1\u5b9a；\u540e\u7eed\u6240\u6709\u6536\u53d1，\u90fd\u7528\u8fd9\u4e2a\u81ea\u52a8\u5206\u914d\u7684\u968f\u673a\u7aef\u53e3\u3002\u670d\u52a1\u7aef\u5fc5\u987b\u624b\u52a8 bind \u56fa\u5b9a\u7aef\u53e3，\u5ba2\u6237\u7aef\u4e0d\u9700\u8981，\u8fd9\u662f UDP \u5ba2\u6237\u7aef\u5f00\u53d1\u7684\u6838\u5fc3\u89c4\u8303\u3002<\/p>\n

      (3). recvfrom \u63a5\u6536\u670d\u52a1\u7aef\u56de\u58f0<\/p>\n

      \"\" \u8fd9\u91cc\u7684 temp \u7ed3\u6784\u4f53，\u7528\u6765\u63a5\u6536\u670d\u52a1\u7aef\u7684 IP + \u7aef\u53e3；<\/span>\u5ba2\u6237\u7aef\u7684 recvfrom \u662f\u975e\u963b\u585e\u7b49\u5f85：\u53ea\u6709\u53d1\u9001\u5b8c\u6570\u636e\u540e，\u624d\u4f1a\u7b49\u5f85\u670d\u52a1\u7aef\u7684\u56de\u58f0；\u670d\u52a1\u7aef\u7684recvfrom\u662f\u6c38\u4e45\u963b\u585e\u7b49\u5f85，\u968f\u65f6\u63a5\u6536\u6240\u6709\u5ba2\u6237\u7aef\u6570\u636e；\u6570\u636e\u63a5\u6536\u903b\u8f91\u548c\u670d\u52a1\u7aef\u5b8c\u5168\u4e00\u81f4：\u4ece\u5ba2\u6237\u7aef socket \u7684\u5185\u6838\u63a5\u6536\u7f13\u51b2\u533a，\u62f7\u8d1d\u6570\u636e\u5230\u7528\u6237\u6001inbuffer\u3002<\/p>\n

      (4). \u6253\u5370\u56de\u58f0\u7ed3\u679c<\/p>\n

      \"\" \u5c06\u670d\u52a1\u7aef\u8fd4\u56de\u7684\u56de\u58f0\u6570\u636e\u6253\u5370\u5230\u7ec8\u7aef，\u5b8c\u6210\u4e00\u6b21 \u201c\u7528\u6237\u8f93\u5165\u2192\u5ba2\u6237\u7aef\u53d1\u9001\u2192\u670d\u52a1\u7aef\u56de\u58f0\u2192\u5ba2\u6237\u7aef\u8f93\u51fa\u201d \u7684\u5b8c\u6574\u4ea4\u4e92\u95ed\u73af\u3002<\/p>\n

      \u8fd0\u884c\u7ed3\u679c :<\/h2>\n

      \u4e0b\u9762\u6211\u4eec\u5c31\u76f4\u63a5\u5c55\u793a\u8fd0\u884c\u7ed3\u679c，\u5c55\u793a UDP \u56de\u58f0\u670d\u52a1\u5668\u5728\u4e09\u79cd\u4e0d\u540c\u8bbf\u95ee\u573a\u666f\u4e0b\u7684\u5b9e\u9645\u8868\u73b0<\/p>\n

      \u672c\u5730\u56de\u73af\u5730\u5740\u901a\u4fe1 (127.0.0.1)<\/h3>\n

      \u8fd0\u884c .\/client_udp 127.0.0.1 8080 \u547d\u4ee4\u540e，\u5728\u5ba2\u6237\u7aef：\u8f93\u5165 "\u4e2d\u5348\u597d" :<\/p>\n

      \"\"<\/p>\n

      \u56de\u8f66\u540e\u7acb\u523b\u6536\u5230\u670d\u52a1\u7aef\u56de\u590d "server echo# \u4e2d\u5348\u597d" :<\/p>\n

      \"\"<\/p>\n

      \"\"<\/p>\n

      \u670d\u52a1\u7aef\u65e5\u5fd7\u6253\u5370\u51fa\u5ba2\u6237\u7aef\u6765\u6e90\u4e3a [127.0.0.1:43677]\u3002\u540c\u65f6\u5c06 "\u4e2d\u5348\u597d" \u8fd4\u56de\u6253\u5370，\u6ce8\u610f\u8fd9\u91cc\u7684\u7aef\u53e3\u53f7 43677 \u662f\u5ba2\u6237\u7aef\u81ea\u52a8\u5206\u914d\u7684\u4e34\u65f6\u7aef\u53e3\u3002<\/p>\n<\/p>\n

      \u8fd9\u662f\u672c\u673a\u5185\u90e8\u901a\u4fe1\u3002\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u7aef\u90fd\u5728\u540c\u4e00\u53f0\u4e3b\u673a\u4e0a\u3002\u800c 127.0.0.1 \u662f\u56de\u73af\u5730\u5740，\u6570\u636e\u4e0d\u7ecf\u8fc7\u771f\u5b9e\u7f51\u5361，\u76f4\u63a5\u5728\u5185\u6838\u91cc\u7ed5\u4e00\u5708\u5c31\u56de\u5230\u4e86\u5ba2\u6237\u7aef\u3002<\/span><\/p>\n

      \u5185\u7f51 IP \u901a\u4fe1 (10.0.16.7)<\/h3>\n

      \u8fd0\u884c .\/client_udp 10.0.16.7 8080 \u540e\u5728\u5ba2\u6237\u7aef：\u8f93\u5165 "\u5403\u4e86\u5417" :<\/p>\n

      \"\"<\/p>\n

      \u56de\u8f66\u540e\u7acb\u523b\u6536\u5230\u670d\u52a1\u7aef\u56de\u590d "server echo# \u5403\u4e86\u5417" :<\/p>\n

      \"\"<\/p>\n

      \"\"<\/p>\n

      \u670d\u52a1\u7aef\u65e5\u5fd7\u6253\u5370\u51fa\u5ba2\u6237\u7aef\u6765\u6e90\u4e3a [10.0.16.7:33657]\u3002\u8fd9\u91cc\u7684\u00a0IP \u53d8\u6210\u4e86\u5185\u7f51 IP\u3002<\/p>\n<\/p>\n

      \u8fd9\u662f\u540c\u4e00\u5c40\u57df\u7f51\u5185\u7684\u673a\u5668\u901a\u4fe1\u3002\u5ba2\u6237\u7aef\u660e\u786e\u6307\u5b9a\u4e86\u670d\u52a1\u7aef\u7684\u5185\u7f51 IP\u3002\u6570\u636e\u7ecf\u8fc7\u4e86\u771f\u5b9e\u7684\u7f51\u5361\u534f\u8bae\u6808\u3002\u5ba2\u6237\u7aef\u62ff\u5230\u7684\u6e90 IP \u662f\u5b83\u53d1\u51fa\u6570\u636e\u5305\u65f6\u7684\u672c\u673a\u7f51\u5361 IP\u3002\u8fd9\u8bc1\u660e\u6211\u4eec\u7684\u670d\u52a1\u7aef\u4ee3\u7801\u4e0d\u662f\u6b7b\u7ed1\u67d0\u4e00\u4e2a IP，\u800c\u662f\u76d1\u542c\u4e86\u6240\u6709\u7f51\u5361（\u5f52\u529f\u4e8e INADDR_ANY），\u6240\u4ee5\u65e0\u8bba\u5ba2\u6237\u7aef\u4ece\u54ea\u4e2a\u7f51\u5361（\u5185\u7f51\u3001\u5916\u7f51）\u53d1\u6765\u6570\u636e，\u670d\u52a1\u7aef\u90fd\u80fd\u6536\u5230\u3002<\/p>\n

      \u516c\u7f51 IP \u901a\u4fe1 (124.222.191.171)<\/h3>\n

      \u8fd0\u884c .\/client_udp 124.222.191.171 8080\u00a0\u540e\u5ba2\u6237\u7aef\u8f93\u5165 "\u4eca\u5929\u8fc7\u5f97\u600e\u4e48\u6837" :<\/p>\n

      \"\"<\/p>\n

      \u56de\u8f66\u540e\u7acb\u523b\u6536\u5230\u670d\u52a1\u7aef\u56de\u590d "server echo# \u4eca\u5929\u8fc7\u5f97\u600e\u4e48\u6837" :<\/p>\n

      \"\"<\/p>\n

      \"\"<\/p>\n

      \u670d\u52a1\u7aef\u65e5\u5fd7\u6253\u5370\u51fa\u5ba2\u6237\u7aef\u6765\u6e90\u4e3a [124.222.191.171:44555]\u3002\u6e90 IP \u53d8\u6210\u4e86\u516c\u7f51 IP\u3002<\/p>\n<\/p>\n

      \u8fd9\u662f\u8de8\u7f51\u7edc\u3001\u8de8\u516c\u7f51\u7684\u901a\u4fe1\u3002\u5ba2\u6237\u7aef\u901a\u8fc7\u516c\u7f51 IP \u627e\u5230\u4e86\u670d\u52a1\u7aef\u3002\u5ba2\u6237\u7aef\u53d1\u9001\u6570\u636e\u65f6，\u5185\u6838\u81ea\u52a8\u5206\u914d\u4e00\u4e2a\u4e34\u65f6\u516c\u7f51\u7aef\u53e3（\u5982 44555）<\/span>\u3002\u6570\u636e\u901a\u8fc7\u7f51\u7edc\u8def\u7531，\u5230\u8fbe\u4e86\u62e5\u6709\u8be5\u516c\u7f51 IP \u7684\u673a\u5668\u3002\u670d\u52a1\u7aef\u6536\u5230\u6570\u636e，\u5e76\u901a\u8fc7\u6570\u636e\u5305\u91cc\u7684\u516c\u7f51 IP + \u4e34\u65f6\u7aef\u53e3，\u786e\u8ba4\u4e86\u5ba2\u6237\u7aef\u8eab\u4efd，\u4ece\u800c\u80fd\u51c6\u786e\u56de\u4fe1\u3002\u8fd9\u4e5f\u662f\u6700\u63a5\u8fd1\u771f\u5b9e\u751f\u4ea7\u73af\u5883\u7684\u6548\u679c\u3002\u670d\u52a1\u7aef\u4ee3\u7801\u652f\u6301\u516c\u7f51\u8bbf\u95ee，\u53ea\u8981\u516c\u7f51 IP \u6620\u5c04\u6b63\u786e，\u670d\u52a1\u7aef\u5c31\u80fd\u63d0\u4f9b\u670d\u52a1\u3002<\/p>\n

      \u5b8c\u6574\u4ee3\u7801 :<\/h2>\n

      EchoServer.hpp<\/p>\n

      #ifndef __ECHOSERVER_HPP
      \n#define __ECHOSERVER_HPP<\/p>\n

      #include <iostream>
      \n#include <string>
      \n#include <cstdlib>
      \n#include <strings.h>
      \n#include <sys\/socket.h>
      \n#include <netinet\/in.h>
      \n#include <arpa\/inet.h>
      \n#include "Logger.hpp"<\/p>\n

      using namespace NS_LOG_MODULE;
      \nconst static int default_fd = -1;
      \nconst static int default_port = 8888;
      \nenum
      \n{
      \n SUCCESS = 0,
      \n USAGE_ERR,
      \n SOCKET_ERR,
      \n BIND_ERR,
      \n};<\/p>\n

      class UdpServer
      \n{
      \npublic:
      \n \/\/ UdpServer(const std::string &ip, uint16_t port = default_port)
      \n UdpServer(uint16_t port = default_port)
      \n : _port(port),
      \n _sockfd(default_fd)
      \n {
      \n }
      \n ~UdpServer()
      \n {
      \n close(_sockfd);
      \n }
      \n void Init()
      \n {
      \n \/\/ \u7b2c\u4e00\u6b65: \u521b\u5efasocket, \u672c\u8d28: \u6253\u5f00\u7f51\u5361 — \u7cfb\u7edf\u7279\u6027
      \n _sockfd = socket(AF_INET, SOCK_DGRAM, 0);
      \n if (_sockfd < 0)
      \n {
      \n LOG(LogLevel::FATAL) << "create socket error";
      \n exit(SOCKET_ERR);
      \n }
      \n LOG(LogLevel::INFO) << "create socket success, sockfd: " << _sockfd;<\/p>\n

      \/\/ \u7b2c\u4e8c\u6b65: \u586b\u5145\u7f51\u7edc\u4fe1\u606f, \u6709\u6ca1\u6709IP\u548c\u7aef\u53e3\u4fe1\u606f\u8bbe\u7f6e\u5230\u5185\u6838\u4e2d？？\u8bbe\u7f6e\u5230\u4f60\u521a\u521a\u6253\u5f00\u7684\u7f51\u7edcsocket\u5bf9\u5e94\u7684\u6587\u4ef6\u5185\u90e8？
      \n struct sockaddr_in local; \/\/ struct sockaddr_in \u6570\u636e\u7c7b\u578b，local \u7528\u6237\u6808\u4e0a\u7684！！！，\u5e76\u6ca1\u6709\u8bbe\u7f6e\u5230\u5185\u6838
      \n bzero(&local, sizeof(local));
      \n local.sin_family = AF_INET;
      \n local.sin_port = htons(_port); \/\/ h->n<\/p>\n

      local.sin_addr.s_addr = INADDR_ANY; \/\/ \u6700\u4f73\u5b9e\u8df5：\u4efb\u610fIP\u5730\u5740bind<\/p>\n

      \/\/ \u7b2c\u4e09\u6b65：bind socket \u4fe1\u606f
      \n int n = bind(_sockfd, (struct sockaddr *)&local, sizeof(local));
      \n if (n < 0)
      \n {
      \n LOG(LogLevel::FATAL) << "bind socket error";
      \n exit(BIND_ERR);
      \n }
      \n LOG(LogLevel::INFO) << "bind socket success"<< ", port: " << _port;
      \n }
      \n void Start()
      \n {
      \n \/\/ \u4f20\u9012\u7684\u662f\u5b57\u7b26\u4e32,echo server
      \n char inbuffer[1024];
      \n while (true)
      \n {
      \n struct sockaddr_in peer;
      \n socklen_t len = sizeof(peer);
      \n \/\/ 1. \u7528\u6237\u53d1\u6765\u7684\u6570\u636e
      \n \/\/ 2. \u7528\u6237\u7684socket\u4fe1\u606f
      \n ssize_t n = recvfrom(_sockfd, inbuffer, sizeof(inbuffer) – 1, 0, (struct sockaddr *)&peer, &len);
      \n if (n > 0)
      \n {
      \n \/\/ 1. \u7f51\u7edc\u5b57\u8282\u5e8f \u2192 \u4e3b\u673a\u5b57\u8282\u5e8f，\u89e3\u6790\u5ba2\u6237\u7aefIP\u548c\u7aef\u53e3
      \n uint16_t client_port = ntohs(peer.sin_port);
      \n std::string client_ip = inet_ntoa(peer.sin_addr); \/\/ 4\u5b57\u8282IP-> ntoh -> \u5b57\u7b26\u4e32
      \n std::string client_address = "[" + client_ip + ":" + std::to_string(client_port) + "]# ";
      \n \/\/ 2. \u7ed9\u63a5\u6536\u6570\u636e\u52a0\u5b57\u7b26\u4e32\u7ed3\u675f\u7b26
      \n inbuffer[n] = '\\\\0';
      \n \/\/ 3. \u65e5\u5fd7\u6253\u5370 + \u5c01\u88c5\u670d\u52a1\u7aef\u8981\u539f\u8def\u8fd4\u56de\u7684\u6570\u636e
      \n LOG(LogLevel::DEBUG) << client_address << inbuffer;
      \n std::string echo_string = "server echo# ";
      \n echo_string += inbuffer;
      \n \/\/ h to n
      \n sendto(_sockfd, echo_string.c_str(), echo_string.size(), 0, (struct sockaddr *)&peer, len);
      \n }
      \n else
      \n {
      \n LOG(LogLevel::ERROR) << "recvfrom error";
      \n }
      \n }
      \n }<\/p>\n

      private:
      \n int _sockfd;
      \n uint16_t _port; \/\/ \u7528\u6237\u8bbe\u7f6e\u597d\u7684，server port\u5fc5\u987b\u662f\u56fa\u5b9a\u7684！
      \n \/\/ std::string _ip; \/\/ "192.168.2.2"
      \n};<\/p>\n

      #endif <\/p>\n

      EchoServerMain.cc<\/p>\n

      #include "EchoServer.hpp"
      \n#include <memory><\/p>\n

      static void Usage(const std::string &process)
      \n{
      \n std::cerr << "Usage:\\\\n\\\\t";
      \n std::cerr << process << " local_port" << std::endl;
      \n}<\/p>\n

      \/\/ .\/server_udp port
      \nint main(int argc, char *argv[])
      \n{
      \n if(argc != 2)
      \n {
      \n Usage(argv[0]);
      \n exit(USAGE_ERR);
      \n }
      \n ENABLE_CONSOLE_LOG_STRATEGY();<\/p>\n

      uint16_t server_port = std::stoi(argv[1]);<\/p>\n

      std::unique_ptr<UdpServer> usvr = std::make_unique<UdpServer>(server_port);
      \n usvr->Init();
      \n usvr->Start();<\/p>\n

      return 0;
      \n} <\/p>\n

      EchoClient.cc<\/p>\n

      #include <iostream>
      \n#include <string>
      \n#include <cstring>
      \n#include <cstdlib>
      \n#include <sys\/socket.h>
      \n#include <arpa\/inet.h>
      \n#include <netinet\/in.h><\/p>\n

      static void Usage(const std::string &proc)
      \n{
      \n std::cout << "Usage:\\\\n\\\\t";
      \n std::cout << proc << " server_ip server_port" << std::endl;
      \n}<\/p>\n

      \/\/ \u6211\u600e\u4e48\u77e5\u9053server\u5bf9\u65b9\u7684IP\u548c\u7aef\u53e3\u554a， \u7c7b\u4f3cIP+Port \u662f\u88ab\u5185\u7f6e\u5230client\u7684！！！
      \n\/\/ .\/client_udp server_ip server_port
      \nint main(int argc, char *argv[])
      \n{
      \n if(argc != 3)
      \n {
      \n Usage(argv[0]);
      \n exit(1);
      \n }
      \n std::string server_ip = argv[1];
      \n uint16_t server_port = std::stoi(argv[2]);<\/p>\n

      \/\/ 1. \u521b\u5efasocket
      \n int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
      \n if(sockfd < 0)
      \n {
      \n std::cerr << "socket error" << std::endl;
      \n exit(2);
      \n }<\/p>\n

      \/\/ 2. \u6784\u5efaserver\u7aefsocket\u4fe1\u606f
      \n \/\/ client \u9700\u8981\u6709\u81ea\u5df1\u7684IP\u548cPort\u4fe1\u606f\u5417? \u9700\u8981\u7684！
      \n \/\/ \u9700\u8981\u663e\u793a\u7684bind\u81ea\u5df1\u7684ip\u548c\u7aef\u53e3\u5417？\u4e0d\u8981\u663e\u793abind！！！
      \n \/\/ 1. \u4e3a\u4ec0\u4e48\u4e0d\u8ba9client\u663e\u793abind？client bind port \u51fa\u73b0\u51b2\u7a81！client port\u53ea\u9700\u8981\u5177\u6709\u552f\u4e00\u6027\u5373\u53ef，\u5177\u4f53\u662f\u51e0，\u4e0d\u91cd\u8981\u3002
      \n \/\/ 2. \u5982\u4f55\u8bbe\u7f6e\u81ea\u5df1\u7684IP\u548c\u7aef\u53e3\u5462？client \u4e00\u822c\u4f1a\u91c7\u7528\u968f\u673a\u7aef\u53e3\u7684\u65b9\u5f0f！\u7531OS\u81ea\u4e3b\u9009\u62e9！
      \n \/\/ udp client \u9996\u6b21\u53d1\u9001\u6570\u636e\u7684\u65f6\u5019，OS\u5e95\u5c42\u4f1a\u9690\u5f0f\u81ea\u52a8\u5e2e\u4f60\u8fdb\u884c\u83b7\u53d6\u968f\u673a\u7aef\u53e3，\u7136\u540ebind + Port + IP
      \n struct sockaddr_in server;
      \n memset(&server, 0, sizeof(0));
      \n server.sin_family = AF_INET;
      \n server.sin_port = htons(server_port);
      \n server.sin_addr.s_addr = inet_addr(server_ip.c_str());<\/p>\n

      while(true)
      \n {
      \n std::string message;
      \n \/\/ 1. \u83b7\u53d6\u7528\u6237\u8f93\u5165
      \n std::cout << "Please Enter# ";
      \n std::getline(std::cin, message);<\/p>\n

      \/\/ 2. clinet \u53d1\u9001\u6570\u636e\u7ed9 server，\u9996\u6b21\u53d1\u9001\u5373\u81ea\u52a8bind
      \n ssize_t n = sendto(sockfd, message.c_str(), message.size(), 0, (struct sockaddr*)&server, sizeof(server));
      \n if(n > 0)
      \n {
      \n \/\/ recvfrom
      \n char inbuffer[1024] = {0};
      \n struct sockaddr_in temp;
      \n socklen_t len = sizeof(temp);
      \n ssize_t m = recvfrom(sockfd, inbuffer, sizeof(inbuffer)-1, 0, (struct sockaddr*)&temp, &len);
      \n if(m > 0)
      \n {
      \n inbuffer[m] = 0;
      \n std::cout << inbuffer << std::endl;
      \n }
      \n }
      \n }<\/p>\n

      return 0;
      \n} <\/p>\n

      \u6a21\u578b\u56fe:<\/h2>\n

      \"\"<\/h2>\n

      \"\"<\/h2>\n

      \u7ed3\u6784\u4f53\u533a\u522b:<\/p>\n

      \"\"<\/h2>\n

      \u603b\u7ed3:<\/h2>\n

      1. \u670d\u52a1\u7aef\u4e4b\u6240\u4ee5\u5fc5\u987b\u7ed1\u5b9a 8080 \u7aef\u53e3，\u662f\u56e0\u4e3a\u670d\u52a1\u7aef\u4f5c\u4e3a\u88ab\u8bbf\u95ee\u65b9，\u9700\u8981\u63d0\u4f9b\u4e00\u4e2a\u56fa\u5b9a\u7684\u7f51\u7edc\u5165\u53e3，\u8fd9\u6837\u5ba2\u6237\u7aef\u624d\u80fd\u627e\u5230\u5b83\u3002\u56e0\u6b64\u5ba2\u6237\u7aef\u5728\u8bbf\u95ee\u65f6，\u5fc5\u987b\u6307\u5b9a 8080 \u7aef\u53e3，\u5c31\u662f\u4e3a\u4e86\u901a\u8fc7\u8fd9\u4e2a\u7aef\u53e3\u7cbe\u51c6\u5b9a\u4f4d\u5230\u670d\u52a1\u7aef\u7a0b\u5e8f\u3002 \u00a0<\/span> 2. \u800c\u5ba2\u6237\u7aef\u5728\u7b2c\u4e00\u6b21\u53d1\u9001\u6570\u636e\u4e4b\u524d，\u5e76\u6ca1\u6709\u81ea\u5df1\u7684\u7aef\u53e3\u3002\u5f53\u5ba2\u6237\u7aef\u7b2c\u4e00\u6b21\u8c03\u7528 sendto\u00a0\u53d1\u9001\u6570\u636e\u65f6，\u64cd\u4f5c\u7cfb\u7edf\u4f1a\u81ea\u52a8\u4e3a\u5ba2\u6237\u7aef\u5206\u914d\u4e00\u4e2a\u968f\u673a\u7684\u4e34\u65f6\u7aef\u53e3\u3002\u8fd9\u4e2a\u4e34\u65f6\u7aef\u53e3\u4f1a\u88ab\u64cd\u4f5c\u7cfb\u7edf\u8bb0\u5f55\u5728\u5bf9\u5e94\u7684\u7ed3\u6784\u4f53\u4e2d，\u5e76\u968f\u7740\u6570\u636e\u5305\u4e00\u8d77\u53d1\u9001\u5230\u670d\u52a1\u7aef\u3002 \u00a0 3. \u670d\u52a1\u7aef\u6536\u5230\u5ba2\u6237\u7aef\u6570\u636e\u540e，\u5c31\u80fd\u4ece\u6570\u636e\u5305\u4e2d\u89e3\u6790\u51fa\u5ba2\u6237\u7aef\u7684 IP + \u4e34\u65f6\u7aef\u53e3，\u5e76\u5728\u56de\u590d\u65f6\u628a\u8fd9\u4e2a\u5730\u5740\u586b\u8fdb\u00a0sendto\u00a0\u7684\u76ee\u6807\u5730\u5740\u91cc\u3002\u8fd9\u6837\u670d\u52a1\u7aef\u5c31\u80fd\u51c6\u786e\u628a\u6570\u636e\u56de\u53d1\u7ed9\u5ba2\u6237\u7aef，\u5b9e\u73b0\u53cc\u65b9\u7684\u53cc\u5411\u901a\u4fe1\u3002 \u00a0 4. \u800c IP \u7684\u4f5c\u7528，\u5c31\u662f\u533a\u5206\u4e0d\u540c\u7684\u7f51\u7edc\u8def\u5f84\u3002\u6bd4\u5982\u901a\u8fc7\u672c\u5730\u56de\u73af \u00a0127.0.0.1\u00a0\u3001\u5185\u7f51 IP\u3001\u6216\u8005\u516c\u7f51 IP \u8fdb\u884c\u8bbf\u95ee\u3002\u4e0d\u7ba1\u662f\u54ea\u4e00\u79cd IP，\u6700\u7ec8\u90fd\u662f\u4e3a\u4e86\u627e\u5230\u90a3\u53f0\u8fd0\u884c\u7740\u670d\u52a1\u7aef\u7a0b\u5e8f\u7684\u673a\u5668，\u518d\u901a\u8fc7 8080 \u7aef\u53e3\u627e\u5230\u5177\u4f53\u7684\u670d\u52a1\u7aef\u8fdb\u7a0b\u3002<\/p>\n<\/p>\n

      5. \u6211\u4eec\u73b0\u5728\u770b\u5230\u7684\u5168\u662f：socket\u3001sendto\u3001recvfrom\u3001\u5185\u6838\u7f13\u51b2\u533a\u3001\u7ed3\u6784\u4f53\u62f7\u8d1d，\u5168\u662f\u672c\u673a\u5185\u90e8\u7684\u7cfb\u7edf\u8c03\u7528\u903b\u8f91，\u770b\u4e0d\u5230\u7f51\u7ebf\u3001\u7f51\u5361\u3001\u8def\u7531\u3001IP \u7f51\u7edc，\u6240\u4ee5\u6211\u4eec\u4f1a\u89c9\u5f97\u201c\u8fd9\u4e0d\u5c31\u662f\u4e24\u4e2a\u7a0b\u5e8f\u901a\u8fc7\u5185\u6838\u7f13\u51b2\u533a\u4e92\u76f8\u62f7\u8d1d\u6570\u636e\u5417？\u548c\u7f51\u7edc\u6709\u5565\u5173\u7cfb？<\/p>\n

      \u00a0 \u00a0 \u00a0\u00a0\u2705 Socket \u4e0d\u662f \u201c\u5185\u5b58\u7f13\u51b2\u533a\u201d，Socket \u662f\u64cd\u4f5c\u7cfb\u7edf\u7ed9\u4f60\u5c01\u88c5\u597d\u7684\u3001\u64cd\u4f5c\u7f51\u5361\u6536\u53d1\u7f51\u7edc\u6570\u636e\u5305\u7684\u7edf\u4e00\u63a5\u53e3\u3002<\/p>\n

      \u00a0 \u00a0 \u00a0 \u2705 \u6211\u4eec\u8c03\u7528 sendto，\u672c\u8d28\u4e0d\u662f \u201c\u62f7\u8d1d\u5230\u5185\u6838\u7f13\u51b2\u533a\u201d，\u800c\u662f：\u544a\u8bc9\u64cd\u4f5c\u7cfb\u7edf，\u628a\u8fd9\u6bb5\u6570\u636e，\u5c01\u88c5\u6210\u6807\u51c6 IP\/UDP \u6570\u636e\u5305，\u901a\u8fc7\u7f51\u5361\u53d1\u51fa\u53bb，\u9001\u5230\u6307\u5b9a IP \u7684\u53e6\u4e00\u53f0\u673a\u5668\u3002<\/p>\n

      \u00a0 \u00a0 \u00a0 \u2705 \u6211\u4eec\u770b\u4e0d\u5230\u7f51\u7ebf\u3001\u770b\u4e0d\u5230\u7f51\u5361，\u662f\u56e0\u4e3a Linux \u5185\u6838\u628a\u7f51\u5361\u9a71\u52a8\u3001\u7f51\u7edc\u534f\u8bae\u3001\u8def\u7531\u8f6c\u53d1\u5168\u90e8\u5c01\u88c5\u5728\u4e86 socket\u3001sendto\u3001recvfrom \u8fd9\u51e0\u4e2a\u7cfb\u7edf\u8c03\u7528\u91cc，\u8c03\u7528\u7684\u4e00\u77ac\u95f4，\u7f51\u7edc\u5c31\u5df2\u7ecf\u53c2\u4e0e\u5de5\u4f5c\u4e86\u3002<\/p>\n

      \u00a0 \u00a0 \u00a0 \u2705 \u771f\u5b9e\u60c5\u51b5\u662f\u6211\u4eec\u5ba2\u6237\u7aef\u8c03\u7528 sendto("\u4e2d\u5348\u597d", \u516c\u7f51IP 124.222.191.171, \u7aef\u53e3\u53f7 8080)，Linux \u5e95\u5c42\u4f1a\u5c01\u88c5 UDP \u6570\u636e\u5305 \u2192 \u901a\u8fc7\u7f51\u5361 \u2192 \u7ecf\u8fc7\u8def\u7531\u5668 \u2192 \u8d70\u771f\u5b9e\u7684\u516c\u7f51 \u2192 \u6570\u636e\u5305\u7a7f\u8fc7\u7f51\u7ebf\u5230\u8fbe \u670d\u52a1\u7aef Linux \u4e3b\u673a\u7684\u7269\u7406\u7f51\u5361 \u2192 \u89e3\u6790 IP + \u7aef\u53e3 \u2192 \u5339\u914d 8080 \u7aef\u53e3\u7684\u670d\u52a1\u7aef Socket\u00a0\u2192 \u6570\u636e\u8fdb\u5165\u670d\u52a1\u7aef Socket \u5185\u6838\u7f13\u51b2\u533a \u2192 recvfrom \u8bfb\u5230\u6570\u636e\u670d\u52a1\u7aef sendto \u56de\u53d1 \u2192 \u53cd\u5411\u8d70\u4e00\u904d\u771f\u5b9e\u7f51\u7edc \u2192 \u56de\u5230 \u5ba2\u6237\u7aef Linux \u4e3b\u673a\u7684\u7269\u7406\u7f51\u5361 \u2192 \u5ba2\u6237\u7aef\u5185\u6838\u89e3\u6790\u5e76\u5339\u914d\u5ba2\u6237\u7aef Socket \u2192 \u6570\u636e\u8fdb\u5165\u5ba2\u6237\u7aef Socket \u5185\u6838\u7f13\u51b2\u533a \u2192 recvfrom \u8bfb\u5230\u54cd\u5e94\u6570\u636e<\/p>\n

      \u8c22\u8c22\u5927\u5bb6\u7684\u89c2\u770b!<\/p>\n","protected":false},"excerpt":{"rendered":"

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