socket学习笔记——并发服务器与I/O程序分割客户端

client.c

 #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);
 void read_routine(int sock,char* buf);
 void write_routine(int sock,char* buf);

 int main(int argc,char* argv[])
 {
     int sock;
     pid_t pid;
     char buf[BUF_SIZE];
     struct sockaddr_in serv_addr;
     if(argc != )
     {
         printf("usage: %s <ip><port>\n",argv[]);
         exit();
     }

     sock = socket(PF_INET,SOCK_STREAM,);
     memset(&serv_addr,,sizeof(serv_addr));
     serv_addr.sin_family = AF_INET;
     serv_addr.sin_addr.s_addr = inet_addr(argv[]);
     serv_addr.sin_port = htons(atoi(argv[]));

     if(connect(sock,(struct sockaddr*)&serv_addr,sizeof(serv_addr)) == -)
         error_handling("connect error");

     pid = fork();
     if(pid == )
         write_routine(sock,buf);
     else
         read_routine(sock,buf);

     close(sock);
     return ;
 }

 void read_routine(int sock,char* buf)
 {
     while()
     {
         int str_len;
         str_len = read(sock,buf,BUF_SIZE);
         if(str_len == )
             return;
         buf[str_len] = ;
         printf("message from server;%s",buf);
     }
 }

 void write_routine(int sock,char* buf)
 {
     while()
     {
         fgets(buf,BUF_SIZE,stdin);
         if(!strcmp(buf,"q\n") || !strcmp(buf,"Q\n"))
         {
             shutdown(sock,SHUT_WR);
             return;
         }
         write(sock,buf,strlen(buf));
     }
 }

 void error_handling(char* message)
 {
     fputs(message,stderr);
     fputc('\n',stderr);
     exit();
 }

server.c

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 #include <signal.h>
 #include <sys/wait.h>
 #include <arpa/inet.h>
 #include <sys/socket.h>

 #define BUF_SIZE 30
 void error_handling(char* message);
 void read_childproc(int sig);

 int main(int argc,char* argv[])
 {
     int serv_sock,clnt_sock;
     struct sockaddr_in serv_addr,clnt_addr;
     struct sigaction act;
     pid_t pid;
     socklen_t adr_sz;
     int str_len ,state;
     char buf[BUF_SIZE];

     if(argc != )
     {
         printf("usage:%s <port>\n",argv[]);
         exit();
     }

     act.sa_handler = read_childproc;
     sigemptyset(&act.sa_mask);
     act.sa_flags = ;
     state = sigaction(SIGCHLD,&act,);

     serv_sock = socket(AF_INET,SOCK_STREAM,);
     memset(&serv_addr,,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[]));

     if(bind(serv_sock,(struct sockaddr*)&serv_addr,sizeof(serv_addr)) == -)
         error_handling("bind error");
     if(listen(serv_sock,) == -)
         error_handling("listen error");

     while()
     {
         adr_sz = sizeof(clnt_addr);
         clnt_sock = accept(serv_sock,(struct sockaddr*)&clnt_addr,&adr_sz);
         if(clnt_sock == -)
             continue;
         else
             puts("connecting......");

         pid = fork();
         if(pid == -)
         {
             close(clnt_sock);
             continue;
         }
         if(pid == )
         {
             close(serv_sock);
             while((str_len = read(clnt_sock,buf,BUF_SIZE)) != )
                 write(clnt_sock,buf,str_len);

             close(clnt_sock);
             return ;
         }
         else
             close(clnt_sock);
     }
     close(serv_sock);
     return ;
 }

 void read_childproc(int sig)
 {
     pid_t pid;
     int status;
     pid = waitpid(-,&status,WNOHANG);
     printf("removed proc id:%d\n",pid);
 }

 void error_handling(char* message)
 {
     fputs(message,stderr);
     fputc('\n',stderr);
     exit();
 }