完成到第三章3.4 P48

ch03/endian_conv.c

@@ -0,0 +1,19 @@
+#include <stdio.h>
+#include <arpa/inet.h>
+int main(int argc, char *argv[])
+{
+    unsigned short host_port = 0x1234;
+    unsigned short net_port;
+    unsigned long host_addr = 0x12345678;
+    unsigned long net_addr;
+
+    net_port = htons(host_port); //转换为网络字节序
+    net_addr = htonl(host_addr);
+
+    printf("Host ordered port: %#x \n", host_port);
+    printf("Network ordered port: %#x \n", net_port);
+    printf("Host ordered address: %#lx \n", host_addr);
+    printf("Network ordered address: %#lx \n", net_addr);
+
+    return 0;
+}

ch03/inet_addr.c

@@ -0,0 +1,20 @@
+#include <stdio.h>
+#include <arpa/inet.h>
+int main(int argc, char *argv[])
+{
+    char *addr1 = "1.2.3.4";
+    char *addr2 = "1.2.3.256";
+
+    unsigned long conv_addr = inet_addr(addr1);
+    if (conv_addr == INADDR_NONE)
+        printf("Error occured! \n");
+    else
+        printf("Network ordered integer addr: %#lx \n", conv_addr);
+
+    conv_addr = inet_addr(addr2);
+    if (conv_addr == INADDR_NONE)
+        printf("Error occured! \n");
+    else
+        printf("Network ordered integer addr: %#lx \n", conv_addr);
+    return 0;
+}

ch03/inet_aton.c

@@ -0,0 +1,23 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <arpa/inet.h>
+void error_handling(char *message);
+
+int main(int argc, char *argv[])
+{
+    char *addr = "127.232.124.79";
+    struct sockaddr_in addr_inet;
+
+    if (!inet_aton(addr, &addr_inet.sin_addr))
+        error_handling("Conversion error");
+    else
+        printf("Network ordered integer addr: %#x \n", addr_inet.sin_addr.s_addr);
+    return 0;
+}
+
+void error_handling(char *message)
+{
+    fputs(message, stderr);
+    fputc('\n', stderr);
+    exit(1);
+}