读书笔记

ch01/hello_client.c

@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+
+void error_handling(char *message);
+
+int main(int argc,char *argv[]){
+	int sock;
+	struct sockaddr_in serv_addr;
+	char message[30];
+	int str_len;
+
+	if(argc != 3){
+		printf("Usage : %s <IP> <port>\n",argv[0]);
+		exit(1);
+	}
+
+	sock = socket(PF_INET,SOCK_STREAM,0);
+	if(sock == -1){
+		error_handling("socket() error");
+	}
+
+	memset(&serv_addr,0,sizeof(serv_addr));
+	serv_addr.sin_family = AF_INET;
+	serv_addr.sin_addr.s_addr = inet_addr(argv[1]);
+	serv_addr.sin_port = htons(atoi(argv[2]));
+
+	if(connect(sock,(struct sockaddr *)&serv_addr,sizeof(serv_addr)) == -1){
+		error_handling("connect() error\r\n");
+	}
+	str_len = read(sock,message,sizeof(message)-1);
+	if(str_len == -1)
+	{
+		error_handling("read() error");
+	}
+
+	printf("Message from server : %s \n",message);
+
+	close(sock);
+	return 0;
+}
+
+void error_handling(char *message){
+	fputs(message,stderr);
+	fputs("\n",stderr);
+	exit(1);
+}

ch01/hello_server.c

@@ -0,0 +1,61 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+
+void error_handling(char *message);
+
+int main(int argc, char *argv[]){
+	int serv_sock;
+	int clnt_sock;
+
+	struct sockaddr_in serv_addr;
+	struct sockaddr_in clnt_addr;
+	socklen_t clnt_addr_size;
+
+	char message[]="hello world!";
+	if(argc != 2){
+		printf("Usage : %s <port>\n",argv[0]);
+		exit(1);
+	}
+	serv_sock = socket(PF_INET,SOCK_STREAM,0);
+	if(serv_sock == -1){
+		error_handling("socket() error");
+	}
+
+	memset(&serv_addr,0,sizeof(serv_addr));
+	serv_addr.sin_family=AF_INET;
+	serv_addr.sin_addr.s_addr=htonl(INADDR_ANY);
+	serv_addr.sin_port=htons(atoi(argv[1]));
+
+	if(bind(serv_sock,(struct sockaddr*)&serv_addr,sizeof(serv_addr)) == -1){
+		error_handling("bind() error");
+	}
+
+	if(listen(serv_sock,5) == -1){
+		error_handling("listen() error");
+	}
+
+	clnt_addr_size = sizeof(clnt_addr);
+	clnt_sock = accept(serv_sock,(struct sockaddr *)&clnt_addr,&clnt_addr_size);
+	if(clnt_sock == -1){
+		error_handling("accept() error");
+	}
+
+	write(clnt_sock,message,sizeof(message));
+
+	close(clnt_sock);
+	close(serv_sock);
+
+	return 0;
+
+}
+
+void error_handling(char *message){
+
+	fputs(message,stderr);
+	fputs("\n",stderr);
+	exit(1);
+}