6.2 UDP的传输特性 P112

ch06/bound_host2.c

@@ -0,0 +1,48 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+
+#define BUF_SIZE 30
+void error_handling(char *message);
+
+int main(int argc, char *argv[])
+{
+    int sock;
+    char msg1[] = "Hi!";
+    char msg2[] = "I'm another UDP host!";
+    char msg3[] = "Nice to meet you";
+
+    struct sockaddr_in your_adr;
+    socklen_t your_adr_sz;
+    if (argc != 3)
+    {
+        printf("Usage : %s <IP> <port>\n", argv[0]);
+        exit(1);
+    }
+    sock = socket(PF_INET, SOCK_DGRAM, 0);
+    if (sock == -1)
+        error_handling("socket() error");
+    memset(&your_adr, 0, sizeof(your_adr));
+    your_adr.sin_family = AF_INET;
+    your_adr.sin_addr.s_addr = inet_addr(argv[1]);
+    your_adr.sin_port = htons(atoi(argv[2]));
+
+    sendto(sock, msg1, sizeof(msg1), 0,
+           (struct sockaddr *)&your_adr, sizeof(your_adr));
+    sendto(sock, msg2, sizeof(msg2), 0,
+           (struct sockaddr *)&your_adr, sizeof(your_adr));
+    sendto(sock, msg3, sizeof(msg3), 0,
+           (struct sockaddr *)&your_adr, sizeof(your_adr));
+    close(sock);
+    return 0;
+}
+
+void error_handling(char *message)
+{
+    fputs(message, stderr);
+    fputc('\n', stderr);
+    exit(1);
+}