47 lines
1.2 KiB
C
47 lines
1.2 KiB
C
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// 编写一个UDP客户端程序, 向服务器发送一个字符串, 并接收服务器返回的字符串并打印出来。
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#include <stdio.h>
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#include <sys/socket.h>
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#include <netinet/in.h>
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#include <arpa/inet.h>
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#include <unistd.h>
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#include <string.h>
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int main(int argc, char const *argv[])
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{
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int sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
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if (sock_fd < 0)
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{
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perror("socket");
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return -1;
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}
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struct sockaddr_in addr;
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bzero(&addr, sizeof(addr));
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addr.sin_family = AF_INET;
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addr.sin_port = htons(8000);
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addr.sin_addr.s_addr = inet_addr("127.0.0.1"); // 指定服务器地址
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// 创建发送的数据
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char buf[128] = "this msg is from client";
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// 发送 udp 数据
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ssize_t n = sendto(sock_fd, buf, strlen(buf), 0, (struct sockaddr *)&addr, sizeof(addr)); // 将 buf 数据发送给服务器
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if (n > 0)
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{
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perror("发送成功\n");
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}
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socklen_t addrlen = sizeof(addr);
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ssize_t recvlen = recvfrom(sock_fd, buf, 128, 0, (struct sockaddr *)&addr, &addrlen); // 从服务器获取数据到 buf
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if (recvlen < 0)
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{
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perror("recvfrom");
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return 1;
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}
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printf("从服务器获取的数据为 %s\n", buf);
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return 0;
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}
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