\u5728\u65e5\u5e38\u5f00\u53d1\u8fc7\u7a0b\u4e2d\uff0c\u6211\u4eec\u5e38\u5e38\u9700\u8981\u8fdb\u884c\u8fdb\u7a0b\u95f4\u901a\u4fe1\u3002\u5176\u4e2d\uff0c\u7f51\u7edc\u901a\u4fe1\u662f\u6700\u5e38\u7528\u7684\u4e00\u79cd\u65b9\u5f0f\u3002\u800c\u5728\u7f51\u7edc\u901a\u4fe1\u4e2d\uff0cUDP\u534f\u8bae\u88ab\u5e7f\u6cdb\u4f7f\u7528\u3002\u672c\u6587\u5c06\u8be6\u7ec6\u4ecb\u7ecd\u5728Linux\u73af\u5883\u4e0b\uff0c\u5982\u4f55\u4f7f\u7528UDP\u534f\u8bae\u8fdb\u884c\u672c\u5730\u901a\u4fe1\u3002<\/p>\n
\u4e00\u3001UDP\u534f\u8bae\u7b80\u4ecb<\/p>\n
UDP\uff08User Datagram Protocol\uff0c\u7528\u6237\u62a5\u6587\u534f\u8bae\uff09\u662f\u4e00\u79cd\u65e0\u8fde\u63a5\u7684\u534f\u8bae\u3002\u5b83\u4e0d\u4f1a\u5efa\u7acb\u8fde\u63a5\uff0c\u76f4\u63a5\u5c06\u6570\u636e\u62a5\u6587\u53d1\u9001\u81f3\u76ee\u7684IP\u5730\u5740\u548c\u7aef\u53e3\u53f7\u3002UDP\u4e0d\u533a\u5206\u5ba2\u6237\u7aef\u548c\u670d\u52a1\u5668\uff0c\u6240\u4ee5\u5728\u901a\u4fe1\u65f6\uff0c\u8981\u5148\u786e\u5b9a\u597d\u901a\u4fe1\u7684\u53cc\u65b9\u7684IP\u5730\u5740\u548c\u7aef\u53e3\u53f7\u3002UDP\u76f8\u5bf9\u4e8eTCP\u66f4\u52a0\u8f7b\u91cf\u7ea7\uff0c\u4f20\u8f93\u6548\u7387\u66f4\u9ad8\uff0c\u4f46\u662f\u5176\u4e0d\u5177\u6709\u53ef\u9760\u6027\u3002\u6570\u636e\u62a5\u6587\u53ef\u80fd\u4f1a\u4e22\u5931\u3001\u91cd\u590d\u3001\u4e71\u5e8f\u7b49\uff0c\u8fd9\u4e9b\u95ee\u9898\u9700\u8981\u5e94\u7528\u7a0b\u5e8f\u81ea\u884c\u5904\u7406\u3002<\/p>\n
\u4e8c\u3001UDP\u534f\u8bae\u7684\u4f18\u7f3a\u70b9<\/p>\n
1. \u4f18\u70b9<\/p>\n
\uff081\uff09\u4f20\u8f93\u6548\u7387\uff1aUDP\u4f7f\u7528\u65e0\u8fde\u63a5\u4f20\u8f93\uff0c\u4e0d\u9700\u8981\u5efa\u7acb\u548c\u65ad\u5f00\u8fde\u63a5\uff0c\u6570\u636e\u62a5\u6587\u7684\u4f20\u8f93\u6548\u7387\u9ad8\uff1b<\/p>\n
\uff082\uff09\u9002\u5408\u6570\u636e\u91cf\u5c0f\u7684\u4f20\u8f93\uff1a\u7531\u4e8eUDP\u534f\u8bae\u6ca1\u6709\u5305\u5934\u548c\u5305\u5c3e\uff0c\u56e0\u6b64\u6570\u636e\u62a5\u6587\u66f4\u52a0\u7d27\u51d1\uff0c\u9002\u5408\u4f20\u8f93\u6570\u636e\u91cf\u5c0f\u7684\u4fe1\u606f\u3002<\/p>\n
2. \u7f3a\u70b9<\/p>\n
\uff081\uff09\u4e0d\u53ef\u9760\uff1aUDP\u534f\u8bae\u4e0d\u63d0\u4f9b\u53ef\u9760\u6027\uff0c\u6570\u636e\u62a5\u6587\u53ef\u80fd\u4e22\u5931\u3001\u91cd\u590d\u3001\u4e71\u5e8f\u7b49\uff1b<\/p>\n
\uff082\uff09\u5e94\u7528\u7a0b\u5e8f\u81ea\u884c\u5904\u7406\uff1aUDP\u534f\u8bae\u4e0d\u63d0\u4f9b\u987a\u5e8f\u63a7\u5236\u548c\u91cd\u4f20\u673a\u5236\uff0c\u8fd9\u4e9b\u95ee\u9898\u9700\u8981\u5e94\u7528\u7a0b\u5e8f\u81ea\u884c\u5904\u7406\uff1b<\/p>\n
\uff083\uff09\u96be\u4ee5\u63a7\u5236\u62e5\u585e\uff1aUDP\u534f\u8bae\u4e0d\u63d0\u4f9b\u62e5\u585e\u63a7\u5236\u673a\u5236\uff0c\u5bf9\u7f51\u7edc\u5e26\u5bbd\u7684\u5229\u7528\u7387\u4e0d\u591f\u9ad8\u3002<\/p>\n
\u4e09\u3001UDP\u534f\u8bae\u7684\u4f7f\u7528<\/p>\n
1. \u521b\u5efaSocket<\/p>\n
\u8981\u4f7f\u7528UDP\u534f\u8bae\u8fdb\u884c\u672c\u5730\u901a\u4fe1\uff0c\u9996\u5148\u9700\u8981\u521b\u5efaSocket\u3002Socket\u662f\u5e94\u7528\u7a0b\u5e8f\u548c\u7f51\u7edc\u4e4b\u95f4\u7684\u4e00\u4e2a\u63a5\u53e3\uff0c\u5b83\u662f\u6570\u636e\u4f20\u8f93\u7684\u901a\u9053\u3002<\/p>\n
int fd = socket(AF_INET, SOCK_DGRAM, 0);<\/p>\n
\u5176\u4e2d\uff0c\u4e4b\u4e00\u4e2a\u53c2\u6570AF_INET\u8868\u793a\u8981\u4f7f\u7528IPv4\u534f\u8bae\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570SOCK_DGRAM\u8868\u793a\u8981\u4f7f\u7528UDP\u534f\u8bae\uff0c\u7b2c\u4e09\u4e2a\u53c2\u65700\u8868\u793a\u7531\u7cfb\u7edf\u81ea\u52a8\u9009\u62e9\u4f7f\u7528\u7684\u534f\u8bae\u3002<\/p>\n
2. \u7ed1\u5b9aIP\u548c\u7aef\u53e3\u53f7<\/p>\n
\u8981\u8fdb\u884c\u672c\u5730\u901a\u4fe1\uff0c\u9700\u8981\u5c06\u672c\u5730\u7684IP\u548c\u7aef\u53e3\u53f7\u4e0eSocket\u7ed1\u5b9a\u3002<\/p>\n
struct sockaddr_in addr;<\/p>\n
addr.sin_family = AF_INET;<\/p>\n
addr.sin_port = htons(8888);<\/p>\n
addr.sin_addr.s_addr = htonl(INADDR_ANY);<\/p>\n
bind(fd, (struct sockaddr*)&addr, sizeof(addr));<\/p>\n
\u5176\u4e2d\uff0c\u4e4b\u4e00\u4e2a\u53c2\u6570fd\u662fSocket\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570\u662f\u4e00\u4e2a\u6307\u5411sockaddr_in\u7ed3\u6784\u4f53\u7684\u6307\u9488\uff0c\u7528\u4e8e\u5b58\u50a8\u7ed1\u5b9a\u7684IP\u548c\u7aef\u53e3\u53f7\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570\u7528\u4e8e\u6307\u5b9asockaddr_in\u7ed3\u6784\u4f53\u7684\u5927\u5c0f\u3002<\/p>\n
3. \u53d1\u9001\u6570\u636e\u62a5\u6587<\/p>\n
\u8981\u53d1\u9001\u6570\u636e\u62a5\u6587\uff0c\u9700\u8981\u6307\u5b9a\u76ee\u6807IP\u5730\u5740\u548c\u7aef\u53e3\u53f7\uff0c\u5c06\u6570\u636e\u5199\u5165Socket\u3002<\/p>\n
struct sockaddr_in dest_addr;<\/p>\n
dest_addr.sin_family = AF_INET;<\/p>\n
dest_addr.sin_port = htons(8888);<\/p>\n
inet_pton(AF_INET, \u201c127.0.0.1\u201d, &dest_addr.sin_addr);<\/p>\n
sendto(fd, buf, len, 0, (struct sockaddr*)&dest_addr, sizeof(dest_addr));<\/p>\n
\u5176\u4e2d\uff0c\u4e4b\u4e00\u4e2a\u53c2\u6570fd\u662fSocket\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570buf\u662f\u8981\u53d1\u9001\u7684\u6570\u636e\u7f13\u51b2\u533a\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570len\u662f\u8981\u53d1\u9001\u7684\u6570\u636e\u957f\u5ea6\uff0c\u7b2c\u56db\u4e2a\u53c2\u65700\u8868\u793a\u4e0d\u9700\u8981\u7279\u6b8a\u7684\u63a7\u5236\uff0c\u7b2c\u4e94\u4e2a\u53c2\u6570\u662f\u4e00\u4e2a\u6307\u5411sockaddr_in\u7ed3\u6784\u4f53\u7684\u6307\u9488\uff0c\u7528\u4e8e\u6307\u5b9a\u76ee\u6807IP\u5730\u5740\u548c\u7aef\u53e3\u53f7\uff0c\u7b2c\u516d\u4e2a\u53c2\u6570\u7528\u4e8e\u6307\u5b9asockaddr_in\u7ed3\u6784\u4f53\u7684\u5927\u5c0f\u3002<\/p>\n
4. \u63a5\u6536\u6570\u636e\u62a5\u6587<\/p>\n
\u8981\u63a5\u6536\u6570\u636e\u62a5\u6587\uff0c\u9700\u8981\u5148\u521b\u5efa\u7f13\u51b2\u533a\uff0c\u7136\u540e\u7b49\u5f85\u63a5\u6536\u6570\u636e\u3002<\/p>\n
char buf[1024];<\/p>\n
struct sockaddr_in src_addr;<\/p>\n
socklen_t src_len = sizeof(src_addr);<\/p>\n
recvfrom(fd, buf, sizeof(buf), 0, (struct sockaddr*)&src_addr, &src_len);<\/p>\n
\u5176\u4e2d\uff0c\u4e4b\u4e00\u4e2a\u53c2\u6570fd\u662fSocket\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570buf\u662f\u7528\u4e8e\u63a5\u6536\u6570\u636e\u7684\u7f13\u51b2\u533a\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570sizeof(buf)\u8868\u793a\u7f13\u51b2\u533a\u7684\u5927\u5c0f\uff0c\u7b2c\u56db\u4e2a\u53c2\u65700\u8868\u793a\u4e0d\u9700\u8981\u7279\u6b8a\u7684\u63a7\u5236\uff0c\u7b2c\u4e94\u4e2a\u53c2\u6570\u662f\u4e00\u4e2a\u6307\u5411sockaddr_in\u7ed3\u6784\u4f53\u7684\u6307\u9488\uff0c\u7528\u4e8e\u5b58\u50a8\u53d1\u9001\u6570\u636e\u62a5\u6587\u65b9\u7684IP\u548c\u7aef\u53e3\u53f7\uff0c\u7b2c\u516d\u4e2a\u53c2\u6570\u7528\u4e8e\u6307\u5b9asockaddr_in\u7ed3\u6784\u4f53\u7684\u5927\u5c0f\u3002<\/p>\n
\u56db\u3001<\/p>\n
\u672c\u6587\u8be6\u7ec6\u4ecb\u7ecd\u4e86\u5728Linux\u73af\u5883\u4e0b\uff0c\u5982\u4f55\u4f7f\u7528UDP\u534f\u8bae\u8fdb\u884c\u672c\u5730\u901a\u4fe1\u3002UDP\u534f\u8bae\u662f\u4e00\u79cd\u65e0\u8fde\u63a5\u7684\u534f\u8bae\uff0c\u4f20\u8f93\u6548\u7387\u9ad8\uff0c\u9002\u5408\u4f20\u8f93\u6570\u636e\u91cf\u5c0f\u7684\u4fe1\u606f\u3002\u4f46\u7531\u4e8e\u5176\u4e0d\u63d0\u4f9b\u53ef\u9760\u6027\u548c\u62e5\u585e\u63a7\u5236\u673a\u5236\uff0c\u9700\u8981\u5e94\u7528\u7a0b\u5e8f\u81ea\u884c\u5904\u7406\u3002<\/p>\n
\u5728\u4f7f\u7528UDP\u534f\u8bae\u8fdb\u884c\u672c\u5730\u901a\u4fe1\u65f6\uff0c\u9700\u8981\u521b\u5efaSocket\uff0c\u7ed1\u5b9aIP\u548c\u7aef\u53e3\u53f7\uff0c\u53d1\u9001\u6570\u636e\u62a5\u6587\u548c\u63a5\u6536\u6570\u636e\u62a5\u6587\u3002\u5728\u53d1\u9001\u548c\u63a5\u6536\u6570\u636e\u62a5\u6587\u65f6\uff0c\u9700\u8981\u6307\u5b9a\u76ee\u6807IP\u5730\u5740\u548c\u7aef\u53e3\u53f7\uff0c\u4ee5\u53ca\u7f13\u51b2\u533a\u5927\u5c0f\u3002\u8fd9\u4e9b\u7ec6\u8282\u9700\u8981\u5f00\u53d1\u4eba\u5458\u638c\u63e1\uff0c\u624d\u80fd\u987a\u5229\u5730\u8fdb\u884c\u672c\u5730\u901a\u4fe1\u3002<\/p>\n
\u76f8\u5173\u95ee\u9898\u62d3\u5c55\u9605\u8bfb\uff1a<\/strong><\/p>\n \u8fd9\u662f\u5728\u7f51\u4e0a\u627e\u5230\u7684\uff0c\u5e0c\u671b\u5bf9\u4f60\u6709\u6240\u5e2e\u52a9\u3002<\/p>\n sockets\uff08\u5957\u63a5\u6570\u795e\u5b57\uff09\u7f16\u7a0b\u6709\u4e09\u79cd\uff0c\u6d41\u5f0f\u5957\u63a5\u5b57\uff08SOCK_STREAM\uff09\uff0c\u6570\u636e\u62a5\u5957\u63a5\u5b57\uff08SOCK_DGRAM\uff09\uff0c\u539f\u59cb\u5957\u63a5\u5b57\uff08SOCK_RAW\uff09\uff1b<\/p>\n WINDOWS\u73af\u5883\u4e0bTCP\/UDP\u7f16\u7a0b\u6b65\u9aa4\uff1a<\/p>\n 1. \u57fa\u4e8e\u88e4\u6bd5\u5ca9TCP\u7684socket\u7f16\u7a0b\u662f\u91c7\u7528\u7684\u6d41\u5f0f\u5957\u63a5\u5b57\u3002<\/p>\n \u5728\u8fd9\u4e2a\u7a0b\u5e8f\u4e2d\uff0c\u5c06\u4e24\u4e2a\u5de5\u7a0b\u6dfb\u52a0\u5230\u4e00\u4e2a\u5de5\u4f5c\u533a\u3002\u8981\u94fe\u63a5\u4e00\u4e2aws2_32.lib\u7684\u5e93\u6587\u4ef6\u3002<\/p>\n \u670d\u52a1\u5668\u7aef\u7f16\u7a0b\u7684\u6b65\u9aa4\uff1a<\/p>\n 1\uff1a\u52a0\u8f7d\u5957\u63a5\u5b57\u5e93\uff0c\u521b\u5efa\u5957\u63a5\u5b57(WSAStartup()\/socket())\uff1b<\/p>\n 2\uff1a\u7ed1\u5b9a\u5957\u63a5\u5b57\u5230\u4e00\u4e2aIP\u5730\u5740\u548c\u4e00\u4e2a\u7aef\u53e3\u4e0a(bind())\uff1b<\/p>\n 3\uff1a\u5c06\u5957\u63a5\u5b57\u8bbe\u7f6e\u4e3a\u76d1\u542c\u6a21\u5f0f\u7b49\u5f85\u8fde\u63a5\u8bf7\u6c42(listen())\uff1b<\/p>\n 4\uff1a\u8bf7\u6c42\u5230\u6765\u540e\uff0c\u63a5\u53d7\u8fde\u63a5\u8bf7\u6c42\uff0c\u8fd4\u56de\u4e00\u4e2a\u65b0\u7684\u5bf9\u5e94\u4e8e\u6b64\u6b21\u8fde\u63a5\u7684\u5957\u63a5\u5b57(accept())\uff1b<\/p>\n 5\uff1a\u7528\u8fd4\u56de\u7684\u5957\u63a5\u5b57\u548c\u5ba2\u6237\u7aef\u8fdb\u884c\u901a\u4fe1(send()\/recv())\uff1b<\/p>\n 6\uff1a\u8fd4\u56de\uff0c\u7b49\u5f85\u53e6\u4e00\u8fde\u63a5\u8bf7\u6c42\uff1b<\/p>\n 7\uff1a\u5173\u95ed\u5957\u63a5\u5b57\uff0c\u5173\u95ed\u52a0\u8f7d\u7684\u5957\u63a5\u5b57\u5e93(closesocket()\/WSACleanup())\u3002<\/p>\n \u670d\u52a1\u5668\u7aef\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n #include <\/p>\n #include <\/p>\n void main()<\/p>\n {<\/p>\n WORD wVersionRequested;<\/p>\n WSADATA wsaData;<\/p>\n int err;<\/p>\n wVersionRequested = MAKEWORD( 1, 1 );<\/p>\n err = WSAStartup( wVersionRequested, &wsaData );<\/p>\n if ( err != 0 ) {<\/p>\n return;<\/p>\n }<\/p>\n if ( LOBYTE( wsaData.wVersion ) != 1 ||<\/p>\n HIBYTE( wsaData.wVersion ) != 1 ) {<\/p>\n WSACleanup( );<\/p>\n return; <\/p>\n }<\/p>\n SOCKET sockSrv=socket(AF_INET,SOCK_STREAM,0);<\/p>\n SOCKADDR_IN addrSrv;<\/p>\n addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY);<\/p>\n addrSrv.sin_family=AF_INET;<\/p>\n addrSrv.sin_port=htons(6000);<\/p>\n bind(sockSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));<\/p>\n listen(sockSrv,5);<\/p>\n SOCKADDR_IN addrClient;<\/p>\n int len=sizeof(SOCKADDR);<\/p>\n while(1)<\/p>\n {<\/p>\n SOCKET sockConn=accept(sockSrv,(SOCKADDR*)&addrClient,&len);<\/p>\n char sendBuf;<\/p>\n<\/p>\n sprintf(sendBuf,\u201dWelcome %s to here!\u201d,inet_ntoa(addrClient.sin_addr));<\/p>\n send(sockConn,sendBuf,strlen(sendBuf)+1,0);<\/p>\n char recvBuf;<\/p>\n<\/p>\n recv(sockConn,recvBuf,50,0);<\/p>\n printf(\u201c%s\\n\u201d,recvBuf);<\/p>\n closesocket(sockConn);<\/p>\n }<\/p>\n }<\/p>\n \u5ba2\u6237\u7aef\u7f16\u7a0b\u7684\u6b65\u9aa4\uff1a<\/p>\n 1\uff1a\u52a0\u8f7d\u5957\u63a5\u5b57\u5e93\uff0c\u521b\u5efa\u5957\u63a5\u5b57(WSAStartup()\/socket())\uff1b<\/p>\n 2\uff1a\u5411\u670d\u52a1\u5668\u53d1\u51fa\u80e1\u5fa1\u8fde\u63a5\u8bf7\u6c42(connect())\uff1b<\/p>\n 3\uff1a\u548c\u670d\u52a1\u5668\u7aef\u8fdb\u884c\u901a\u4fe1(send()\/recv())\uff1b<\/p>\n 4\uff1a\u5173\u95ed\u5957\u63a5\u5b57\uff0c\u5173\u95ed\u52a0\u8f7d\u7684\u5957\u63a5\u5b57\u5e93(closesocket()\/WSACleanup())\u3002<\/p>\n \u5ba2\u6237\u7aef\u7684\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n #include <\/p>\n #include <\/p>\n void main()<\/p>\n {<\/p>\n WORD wVersionRequested;<\/p>\n WSADATA wsaData;<\/p>\n int err;<\/p>\n wVersionRequested = MAKEWORD( 1, 1 );<\/p>\n err = WSAStartup( wVersionRequested, &wsaData );<\/p>\n if ( err != 0 ) {<\/p>\n return;<\/p>\n }<\/p>\n if ( LOBYTE( wsaData.wVersion ) != 1 ||<\/p>\n HIBYTE( wsaData.wVersion ) != 1 ) {<\/p>\n WSACleanup( );<\/p>\n return; <\/p>\n }<\/p>\n SOCKET sockClient=socket(AF_INET,SOCK_STREAM,0);<\/p>\n SOCKADDR_IN addrSrv;<\/p>\n addrSrv.sin_addr.S_un.S_addr=inet_addr(\u201c127.0.0.1\u201d);<\/p>\n addrSrv.sin_family=AF_INET;<\/p>\n addrSrv.sin_port=htons(6000);<\/p>\n connect(sockClient,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));<\/p>\n char recvBuf;<\/p>\n<\/p>\n recv(sockClient,recvBuf,50,0);<\/p>\n printf(\u201c%s\\n\u201d,recvBuf);<\/p>\n send(sockClient,\u201dhello\u201d,strlen(\u201chello\u201d)+1,0);<\/p>\n closesocket(sockClient);<\/p>\n WSACleanup();<\/p>\n } <\/p>\n 2.\u57fa\u4e8eUDP\u7684socket\u7f16\u7a0b\u662f\u91c7\u7528\u7684\u6570\u636e\u62a5\u5957\u63a5\u5b57\u3002<\/p>\n \u5728\u8fd9\u4e2a\u7a0b\u5e8f\u4e2d\uff0c\u5c06\u4e24\u4e2a\u5de5\u7a0b\u6dfb\u52a0\u5230\u4e00\u4e2a\u5de5\u4f5c\u533a\u3002\u540c\u65f6\u8fd8\u8981\u94fe\u63a5\u4e00\u4e2aws2_32.lib\u7684\u5e93\u6587\u4ef6\u3002<\/p>\n \u670d\u52a1\u5668\u7aef\u7f16\u7a0b\u7684\u6b65\u9aa4\uff1a<\/p>\n 1\uff1a\u52a0\u8f7d\u5957\u63a5\u5b57\u5e93\uff0c\u521b\u5efa\u5957\u63a5\u5b57(WSAStartup()\/socket())\uff1b<\/p>\n 2\uff1a\u7ed1\u5b9a\u5957\u63a5\u5b57\u5230\u4e00\u4e2aIP\u5730\u5740\u548c\u4e00\u4e2a\u7aef\u53e3\u4e0a(bind())\uff1b<\/p>\n 3\uff1a\u7b49\u5f85\u548c\u63a5\u6536\u6570\u636e(sendto()\/recvfrom())\uff1b<\/p>\n 4\uff1a\u5173\u95ed\u5957\u63a5\u5b57\uff0c\u5173\u95ed\u52a0\u8f7d\u7684\u5957\u63a5\u5b57\u5e93(closesocket()\/WSACleanup())\u3002<\/p>\n \u670d\u52a1\u5668\u7aef\u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n #include <\/p>\n #include <\/p>\n void main()<\/p>\n {<\/p>\n WORD wVersionRequested;<\/p>\n WSADATA wsaData;<\/p>\n int err;<\/p>\n wVersionRequested = MAKEWORD( 1, 1 );<\/p>\n err = WSAStartup( wVersionRequested, &wsaData );<\/p>\n if ( err != 0 )<\/p>\n {<\/p>\n return;<\/p>\n }<\/p>\n if ( LOBYTE( wsaData.wVersion ) != 1 ||<\/p>\n HIBYTE( wsaData.wVersion ) != 1 )<\/p>\n {<\/p>\n WSACleanup( );<\/p>\n return; <\/p>\n }<\/p>\n SOCKET sockSrv=socket(AF_INET,SOCK_DGRAM,0);<\/p>\n SOCKADDR_IN addrSrv;<\/p>\n addrSrv.sin_addr.S_un.S_addr=htonl(INADDR_ANY);<\/p>\n addrSrv.sin_family=AF_INET;<\/p>\n addrSrv.sin_port=htons(7003);<\/p>\n bind(sockSrv,(SOCKADDR*)&addrSrv,sizeof(SOCKADDR));<\/p>\n char recvBuf;<\/p>\n<\/p>\n SOCKADDR addrClient;<\/p>\n int len=sizeof(SOCKADDR);<\/p>\n recvfrom(sockSrv,recvBuf,50,0,(SOCKADDR*)&addrClient,&len);<\/p>\n printf(\u201c%s\\n\u201d,recvBuf);<\/p>\n closesocket(sockSrv);<\/p>\n WSACleanup();<\/p>\n }<\/p>\n \u5bf9\u4e8e\u57fa\u4e8eUDP\u7684socket\u5ba2\u6237\u7aef\u6765\u8bf4\uff0c\u8981\u8fdb\u884c\u5982\u4e0b\u6b65\u9aa4\uff1a<\/p>\n 1\uff1a\u521b\u5efa\u4e00\u4e2a\u5957\u63a5\u5b57(socket)\uff1b<\/p>\n 2\uff1a\u5411\u670d\u52a1\u5668\u53d1\u9001\u6570\u636e(sendto);<\/p>\n 3\uff1a\u5173\u95ed\u5957\u63a5\u5b57\uff1b<\/p>\n \u4ee3\u7801\u5982\u4e0b\uff1a<\/p>\n #include <\/p>\n #include <\/p>\n void main()<\/p>\n {<\/p>\n WORD wVersionRequested;<\/p>\n WSADATA wsaData;<\/p>\n int err;<\/p>\n wVersionRequested = MAKEWORD( 2, 2 );<\/p>\n err = WSAStartup( wVersionRequested, &wsaData );<\/p>\n if ( err != 0 ) {<\/p>\n return;<\/p>\n }<\/p>\n if ( LOBYTE( wsaData.wVersion ) != 2 ||<\/p>\n HIBYTE( wsaData.wVersion ) != 2 ) {<\/p>\n WSACleanup( );<\/p>\n return; <\/p>\n }<\/p>\n SOCKET sockClient=socket(AF_INET,SOCK_DGRAM,0);<\/p>\n SOCKADDR_IN addrClient;<\/p>\n addrClient.sin_addr.S_un.S_addr=inet_addr(\u201c127.0.0.1\u201d);<\/p>\n addrClient.sin_family=AF_INET;<\/p>\n addrClient.sin_port=htons(8889);<\/p>\n SOCKADDR_IN addrSrv;<\/p>\n sendto(sockClient,\u201dhi\u201d,3,0,(SOCKADDR*)&addrClient,sizeof(SOCKADDR));<\/p>\n }<\/p>\n LINUX\u73af\u5883\u4e0bTCP\/UDP\u7f16\u7a0b\u6b65\u9aa4\uff1a<\/p>\n TCP\u7f16\u7a0b\u6b65\u9aa4\uff1a<\/p>\n \u4e00. \u670d\u52a1\u7aef\uff1a<\/p>\n 1.socket(int domain,int type,int protocol):\u5efa\u7acb\u5957\u63a5\u5b57\uff1b<\/p>\n 2 .bind(int sockid,struct sockaddr *addrp,socklen_t addrlen):\u628a\u672c\u673a\u5730\u5740\u548c\u7aef\u53e3\u8ddf\u4e0a\u4e00\u6b65\u5efa\u7acb\u7684socket\u7ed1\u5b9a\u5728\u4e00\u8d77\uff1b<\/p>\n 3.listen(int sockid,int qsize):\u76d1\u542c\u67d0\u5957\u63a5\u5b57;<\/p>\n 4.fd=accept(int sockid,struct sockaddr *callerid,socklen_t *addrlenp):\u7b49\u5f85\u67d0\u5957\u63a5\u5b57\u63a5\u6536\u4fe1\u606f\uff1b<\/p>\n 5.recv(int fd,void *buf,size_t nbytes,int flags):\u4ece\u5957\u63a5\u5b57\u63a5\u6536\u6570\u636e;<\/p>\n 6.close(fd) \u548cclose(sockid) <\/p>\n \u4e8c.\u5ba2\u6237\u7aef\uff1a<\/p>\n 1. socket():\u5efa\u7acb\u5957\u63a5\u5b57\uff1b<\/p>\n 2.connect(int sockid,struct sockaddr *serv_addrp,socklen_t addrlen):\u8fde\u63a5\u5230\u670d\u52a1\u5668\uff1b<\/p>\n 3. send(int sockfd,const void *buf,size_t nbytes,int flags):\u53d1\u9001\u6570\u636e\u5230\u670d\u52a1\u5668.<\/p>\n 4. close(sockid);<\/p>\n UDP\u7f16\u7a0b\u6b65\u9aa4\uff1a<\/p>\n \u4e00\uff0c\u670d\u52a1\u7aef\uff1a<\/p>\n 1. socket():\u540c\u4e0a\uff1b<\/p>\n 2. bind():\u540c\u4e0a\uff1b<\/p>\n 3. recvfrom(int sockfd,void*buff,size_t nbytes,int flags,struct sockaddr*from,socklen_t*addrlen):\u5728\u5957\u63a5\u5b57\u53e3\u63a5\u6536\u6570\u636e\uff0c\u5e76\u4e14\u8bb0\u5f55\u4e0b\u63a5\u6536\u5230\u7684\u6570\u636e\u6765\u6e90;\u4e00\u5b9a\u8981\u6ce8\u610f\u8fd9\u91cc\u7684\u53c2\u6570addrlen\uff0c\u5b83\u4e0d\u4ec5\u662f\u51fd\u6570\u7684\u8f93\u51fa\uff0c\u4e5f\u662f\u51fd\u6570\u7684\u8f93\u5165\uff01\u6240\u4ee5\u8981\u5728\u8c03\u7528\u8be5\u51fd\u6570\u4e4b\u524d\u5bf9addrlen\u8d4b\u503csizeof(struct sockaddr)\u3002\u5426\u5219\u8fd4\u56de\u7684\u5730\u5740from\u5c06\u4f1a\u51fa\u9519\uff01<\/p>\n 4. close(sockfd);<\/p>\n \u4e8c. \u5ba2\u6237\u7aef\uff1a<\/p>\n 1. socket();\u540c\u4e0a\uff1b<\/p>\n 2. sendto(int sockfd,const void*buff,size_t nbytes,int flags,const struct sockaddr*to,socklen_t addrlen):\u5f80\u6307\u5b9a\u7684\u5730\u5740\u53d1\u9001\u6570\u636e\uff1b<\/p>\n 3. close(sockfd);<\/p>\n UDP Server\u7a0b\u5e8f<\/p>\n 1\u3001\u7f16\u5199UDP Server\u7a0b\u5e8f\u7684\u6b65\u9aa4<\/p>\n (1)\u4f7f\u7528socket()\u6765\u5efa\u7acb\u4e00\u4e2aUDP socket\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570\u4e3aSOCK_DGRAM\u3002<\/p>\n (2)\u521d\u59cb\u5316sockaddr_in\u7ed3\u6784\u7684\u53d8\u91cf\uff0c\u5e76\u8d4b\u503c\u3002sockaddr_in\u7ed3\u6784\u5b9a\u4e49\uff1a<\/p>\n struct sockaddr_in {<\/p>\n uint8_t sin_len;<\/p>\n sa_family_t sin_family;<\/p>\n in_port_t sin_port;<\/p>\n struct in_addr sin_addr;<\/p>\n char sin_zero;<\/p>\n<\/p>\n };<\/p>\n \u8fd9\u91cc\u4f7f\u7528\u201c08\u201d\u4f5c\u4e3a\u670d\u52a1\u7a0b\u5e8f\u7684\u7aef\u53e3\uff0c\u4f7f\u7528\u201cINADDR_ANY\u201d\u4f5c\u4e3a\u59ff\u51ef\u7ed1\u5b9a\u7684IP\u5730\u5740\u5373\u4efb\u4f55\u4e3b\u673a\u4e0a\u7684\u5730\u5740\u3002<\/p>\n (3)\u4f7f\u7528bind()\u628a\u4e0a\u9762\u7684socket\u548c\u5b9a\u4e49\u7684IP\u5730\u5740\u548c\u7aef\u53e3\u7ed1\u5b9a\u3002\u8fd9\u91cc\u68c0\u67e5bind()\u662f\u5426\u6267\u884c\u6210\u529f\uff0c\u5982\u679c\u6709\u9519\u8bef\u5c31\u9000\u51fa\u3002\u8fd9\u6837\u53ef\u4ee5\u9632\u6b62\u670d\u52a1\u7a0b\u5e8f\u91cd\u590d\u8fd0\u884c\u7684\u95ee\u9898\u3002<\/p>\n (4)\u8fdb\u5165\u65e0\u9650\u5faa\u73af\u7a0b\u5e8f\uff0c\u4f7f\u7528recvfrom()\u8fdb\u5165\u7b49\u5f85\u72b6\u6001\uff0c\u76f4\u5230\u63a5\u6536\u5230\u5ba2\u6237\u7a0b\u5e8f\u53d1\u9001\u7684\u6570\u636e\uff0c\u5c31\u5904\u7406\u6536\u5230\u7684\u6570\u636e\uff0c\u5e76\u5411\u5ba2\u6237\u7a0b\u5e8f\u53d1\u9001\u53cd\u9988\u3002\u8fd9\u91cc\u662f\u76f4\u63a5\u628a\u6536\u5230\u7684\u6570\u636e\u53d1\u56de\u7ed9\u5ba2\u6237\u7a0b\u5e8f\u3002<\/p>\n 2\u3001udpserv.c\u7a0b\u5e8f\u5185\u5bb9\uff1a<\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #define MAXLINE 80<\/p>\n #define SERV_PORT 8888<\/p>\n void do_echo(int sockfd, struct sockaddr *pcliaddr, socklen_t clilen)<\/p>\n {<\/p>\n int n;<\/p>\n socklen_t len;<\/p>\n char mesg;<\/p>\n<\/p>\n for(;;)<\/p>\n {<\/p>\n len = clilen;<\/p>\n \/* waiting for receive data *\/<\/p>\n n = recvfrom(sockfd, mesg, MAXLINE, 0, pcliaddr, &len);<\/p>\n \/* sent data back to client *\/<\/p>\n sendto(sockfd, mesg, n, 0, pcliaddr, len);<\/p>\n }<\/p>\n }<\/p>\n int main(void)<\/p>\n {<\/p>\n int sockfd;<\/p>\n struct sockaddr_in servaddr, cliaddr;<\/p>\n sockfd = socket(AF_INET, SOCK_DGRAM, 0); \/* create a socket *\/<\/p>\n \/* init servaddr *\/<\/p>\n bzero(&servaddr, sizeof(servaddr));<\/p>\n servaddr.sin_family = AF_INET;<\/p>\n servaddr.sin_addr.s_addr = htonl(INADDR_ANY);<\/p>\n servaddr.sin_port = htons(SERV_PORT);<\/p>\n \/* bind address and port to socket *\/<\/p>\n if(bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) == -1)<\/p>\n {<\/p>\n perror(\u201cbind error\u201d);<\/p>\n exit(1);<\/p>\n }<\/p>\n do_echo(sockfd, (struct sockaddr *)&cliaddr, sizeof(cliaddr));<\/p>\n return 0;<\/p>\n }<\/p>\n UDP Client\u7a0b\u5e8f<\/p>\n 1\u3001\u7f16\u5199UDP Client\u7a0b\u5e8f\u7684\u6b65\u9aa4<\/p>\n (1)\u521d\u59cb\u5316sockaddr_in\u7ed3\u6784\u4e3e\u518c\u4f0d\u7684\u53d8\u91cf\uff0c\u5e76\u8d4b\u503c\u3002\u8fd9\u91cc\u4f7f\u7528\u201c8888\u201d\u4f5c\u4e3a\u8fde\u63a5\u7684\u670d\u52a1\u7a0b\u5e8f\u7684\u7aef\u53e3\uff0c\u4ece\u547d\u4ee4\u884c\u53c2\u6570\u8bfb\u53d6IP\u5730\u5740\uff0c\u5e76\u4e14\u5224\u65adIP\u5730\u5740\u662f\u5426\u7b26\u5408\u8981\u6c42\u3002<\/p>\n (2)\u4f7f\u7528socket()\u6765\u5efa\u7acb\u4e00\u4e2aUDP socket\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570\u4e3aSOCK_DGRAM\u3002<\/p>\n (3)\u4f7f\u7528connect()\u6765\u5efa\u7acb\u4e0e\u670d\u52a1\u7a0b\u5e8f\u7684\u8fde\u63a5\u3002\u4e0eTCP\u534f\u8bae\u4e0d\u540c\uff0cUDP\u7684connect()\u5e76\u6ca1\u6709\u4e0e\u670d\u52a1\u7a0b\u5e8f\u4e09\u6b21\u63e1\u624b\u3002\u4e0a\u9762\u6211\u4eec\u8bf4\u4e86UDP\u662f\u975e\u8fde\u63a5\u7684\uff0c\u5b9e\u9645\u4e0a\u4e5f\u53ef\u4ee5\u662f\u8fde\u63a5\u7684\u3002\u4f7f\u7528\u8fde\u63a5\u7684UDP\uff0ckernel\u53ef\u4ee5\u76f4\u63a5\u8fd4\u56de\u9519\u8bef\u4fe1\u606f\u7ed9\u7528\u6237\u7a0b\u5e8f\uff0c\u4ece\u800c\u907f\u514d\u7531\u4e8e\u6ca1\u6709\u63a5\u6536\u5230\u6570\u636e\u800c\u5bfc\u81f4\u8c03\u7528recvfrom()\u4e00\u76f4\u7b49\u5f85\u4e0b\u53bb\uff0c\u770b\u4e0a\u53bb\u597d\u50cf\u5ba2\u6237\u7a0b\u5e8f\u6ca1\u6709\u53cd\u5e94\u4e00\u6837\u3002<\/p>\n (4)\u5411\u670d\u52a1\u7a0b\u5e8f\u53d1\u9001\u6570\u636e\uff0c\u56e0\u4e3a\u4f7f\u7528\u8fde\u63a5\u7684UDP\uff0c\u6240\u4ee5\u4f7f\u7528write()\u6765\u66ff\u4ee3sendto()\u3002\u8fd9\u91cc\u7684\u6570\u636e\u76f4\u63a5\u4ece\u6807\u51c6\u8f93\u5165\u8bfb\u53d6\u7528\u6237\u8f93\u5165\u3002\u6b63\u6216<\/p>\n (5)\u63a5\u6536\u670d\u52a1\u7a0b\u5e8f\u53d1\u56de\u7684\u6570\u636e\uff0c\u540c\u6837\u4f7f\u7528read()\u6765\u66ff\u4ee3recvfrom()\u3002<\/p>\n (6)\u5904\u7406\u63a5\u6536\u5230\u7684\u6570\u636e\uff0c\u8fd9\u91cc\u662f\u76f4\u63a5\u8f93\u51fa\u5230\u6807\u51c6\u8f93\u51fa\u4e0a\u3002<\/p>\n 2\u3001udpclient.c\u7a0b\u5e8f\u5185\u5bb9\uff1a<\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #include <\/p>\n #define MAXLINE 80<\/p>\n #define SERV_PORT 8888<\/p>\n void do_cli(FILE *fp, int sockfd, struct sockaddr *pservaddr, socklen_t servlen)<\/p>\n {<\/p>\n int n;<\/p>\n char sendline, recvline;<\/p>\n<\/p>\n \/* connect to server *\/<\/p>\n if(connect(sockfd, (struct sockaddr *)pservaddr, servlen) == -1)<\/p>\n {<\/p>\n perror(\u201cconnect error\u201d);<\/p>\n exit(1);<\/p>\n }<\/p>\n while(fgets(sendline, MAXLINE, fp) != NULL)<\/p>\n {<\/p>\n \/* read a line and send to server *\/<\/p>\n write(sockfd, sendline, strlen(sendline));<\/p>\n \/* receive data from server *\/<\/p>\n n = read(sockfd, recvline, MAXLINE);<\/p>\n if(n == -1)<\/p>\n {<\/p>\n perror(\u201cread error\u201d);<\/p>\n exit(1);<\/p>\n }<\/p>\n recvline = 0; \/* terminate string *\/<\/p>\n<\/p>\n fputs(recvline, stdout);<\/p>\n }<\/p>\n }<\/p>\n int main(int argc, char **argv)<\/p>\n {<\/p>\n int sockfd;<\/p>\n struct sockaddr_in srvaddr;<\/p>\n \/* check args *\/<\/p>\n if(argc != 2)<\/p>\n {<\/p>\n printf(\u201cusage: udpclient \\n\u201d);<\/p>\n exit(1);<\/p>\n }<\/p>\n \/* init servaddr *\/<\/p>\n bzero(&servaddr, sizeof(servaddr));<\/p>\n servaddr.sin_family = AF_INET;<\/p>\n servaddr.sin_port = htons(SERV_PORT);<\/p>\n if(inet_pton(AF_INET, argv, &servaddr.sin_addr) <\/p>\n<\/p>\n {<\/p>\n printf(\u201d is not a valid IPaddress\\n\u201d, argv);<\/p>\n exit(1);<\/p>\n }<\/p>\n sockfd = socket(AF_INET, SOCK_DGRAM, 0);<\/p>\n do_cli(stdin, sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));<\/p>\n return 0;<\/p>\n }<\/p>\n \u8fd0\u884c\u4f8b\u5b50\u7a0b\u5e8f<\/p>\n 1\u3001\u7f16\u8bd1\u4f8b\u5b50\u7a0b\u5e8f<\/p>\n \u4f7f\u7528\u5982\u4e0b\u547d\u4ee4\u6765\u7f16\u8bd1\u4f8b\u5b50\u7a0b\u5e8f\uff1a<\/p>\n gcc -Wall -o udpserv udpserv.c<\/p>\n gcc -Wall -o udpclient udpclient.c<\/p>\n \u7f16\u8bd1\u5b8c\u6210\u751f\u6210\u4e86udpserv\u548cudpclient\u4e24\u4e2a\u53ef\u6267\u884c\u7a0b\u5e8f\u3002<\/p>\n 2\u3001\u8fd0\u884cUDP Server\u7a0b\u5e8f<\/p>\n \u6267\u884c.\/udpserv &\u547d\u4ee4\u6765\u542f\u52a8\u670d\u52a1\u7a0b\u5e8f\u3002\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528netstat -ln\u547d\u4ee4\u6765\u89c2\u5bdf\u670d\u52a1\u7a0b\u5e8f\u7ed1\u5b9a\u7684IP\u5730\u5740\u548c\u7aef\u53e3\uff0c\u90e8\u5206\u8f93\u51fa\u4fe1\u606f\u5982\u4e0b\uff1a<\/p>\n Active Internet connections (only servers)<\/p>\n Proto Recv-Q Send-Q Local Address Foreign Address State<\/p>\n tcp 0 0 0.0.0.0:.0.0.0:* LISTEN<\/p>\n tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN<\/p>\n tcp 0 0 0.0.0.0:6000 0.0.0.0:* LISTEN<\/p>\n tcp.0.0.1:631 0.0.0.0:* LISTEN<\/p>\n udp 0 0 0.0.0.0:.0.0.0:*<\/p>\n udp 0 0 0.0.0.0:8888 0.0.0.0:*<\/p>\n udp 0 0 0.0.0.0:111 0.0.0.0:*<\/p>\n udp 0 0 0.0.0.0:882 0.0.0.0:*<\/p>\n \u53ef\u4ee5\u770b\u5230udp\u5904\u6709\u201c0.0.0.0:8888\u201d\u7684\u5185\u5bb9\uff0c\u8bf4\u660e\u670d\u52a1\u7a0b\u5e8f\u5df2\u7ecf\u6b63\u5e38\u8fd0\u884c\uff0c\u53ef\u4ee5\u63a5\u6536\u4e3b\u673a\u4e0a\u4efb\u4f55IP\u5730\u5740\u4e14\u7aef\u53e3\u4e3a8888\u7684\u6570\u636e\u3002<\/p>\n \u5982\u679c\u8fd9\u65f6\u518d\u6267\u884c.\/udpserv &\u547d\u4ee4\uff0c\u5c31\u4f1a\u770b\u5230\u5982\u4e0b\u4fe1\u606f\uff1a<\/p>\n bind error: Address already in use<\/p>\n \u8bf4\u660e\u5df2\u7ecf\u6709\u4e00\u4e2a\u670d\u52a1\u7a0b\u5e8f\u5728\u8fd0\u884c\u4e86\u3002<\/p>\n 3\u3001\u8fd0\u884cUDP Client\u7a0b\u5e8f<\/p>\n \u6267\u884c.\/udpclient 127.0.0.1\u547d\u4ee4\u6765\u542f\u52a8\u5ba2\u6237\u7a0b\u5e8f\uff0c\u4f7f\u7528127.0.0.1\u6765\u8fde\u63a5\u670d\u52a1\u7a0b\u5e8f\uff0c\u6267\u884c\u6548\u679c\u5982\u4e0b\uff1a<\/p>\n Hello, World!<\/p>\n Hello, World!<\/p>\n this is a test<\/p>\n this is a test<\/p>\n ^d<\/p>\n \u8f93\u5165\u7684\u6570\u636e\u90fd\u6b63\u786e\u4ece\u670d\u52a1\u7a0b\u5e8f\u8fd4\u56de\u4e86\uff0c\u6309ctrl+d\u53ef\u4ee5\u7ed3\u675f\u8f93\u5165\uff0c\u9000\u51fa\u7a0b\u5e8f\u3002<\/p>\n \u5982\u679c\u670d\u52a1\u7a0b\u5e8f\u6ca1\u6709\u542f\u52a8\uff0c\u800c\u6267\u884c\u5ba2\u6237\u7a0b\u5e8f\uff0c\u5c31\u4f1a\u770b\u5230\u5982\u4e0b\u4fe1\u606f\uff1a<\/p>\n $ .\/udpclient 127.0.0.1<\/p>\n test<\/p>\n read error: Connection refused<\/p>\n \u8bf4\u660e\u6307\u5b9a\u7684IP\u5730\u5740\u548c\u7aef\u53e3\u6ca1\u6709\u670d\u52a1\u7a0b\u5e8f\u7ed1\u5b9a\uff0c\u5ba2\u6237\u7a0b\u5e8f\u5c31\u9000\u51fa\u4e86\u3002\u8fd9\u5c31\u662f\u4f7f\u7528connect()\u7684\u597d\u5904\uff0c\u6ce8\u610f\uff0c\u8fd9\u91cc\u9519\u8bef\u4fe1\u606f\u662f\u5728\u5411\u670d\u52a1\u7a0b\u5e8f\u53d1\u9001\u6570\u636e\u540e\u6536\u5230\u7684\uff0c\u800c\u4e0d\u662f\u5728\u8c03\u7528connect()\u65f6\u3002\u5982\u679c\u4f60\u4f7f\u7528tcpdump\u7a0b\u5e8f\u6765\u6293\u5305\uff0c\u4f1a\u53d1\u73b0\u6536\u5230\u7684\u662fICMP\u7684\u9519\u8bef\u4fe1\u606f\u3002<\/p>\n\n
UDP\u548cSocket\u901a\u4fe1\u6b65\u9aa4<\/h3>\n