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Linux下进程通信

学习linux已经有一段时间了，通过下边这个小项目来巩固一下所学知识。这是一个服务器与客户端进行通信的小练习，服务器处于开启状态，客户端进行连接，连接成功后，两者可以发送消息，双方都能收到对方的消息，实现一个小型聊天系统，可以有多个客户端，连接到服务器，也可以发送给服务器信息，目前做到的只是服务器与客户端的收发消息，客户端与客户端还不可以收发消息，在学习深入之后，再将代码进行优化。

先来看一下运行效果

下面的是服务器的代码

#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<string.h>
#include<unistd.h>

int main(int argc,char **argv)
{
        int s_fd;
        int c_fd;
        int n_read;
        char readBuf[128];
        //char *msg = "I get your connect\n";
        char msg[128]={0};

        struct sockaddr_in s_addr;
        struct sockaddr_in c_addr;
        if(argc !=3){
                printf("param is not good\n");
                exit(-1);
        }


        memset(&s_addr,0,sizeof(struct sockaddr_in));memset(&c_addr,0,sizeof(struct sockaddr_in));

        //1.socket
        s_fd = socket(AF_INET,SOCK_STREAM,0);
        if(s_fd == -1){
                perror("socket");
                exit(-1);
        }
        s_addr.sin_family = AF_INET;
        s_addr.sin_port = htons(atoi(argv[2]));
        inet_aton(argv[1],&s_addr.sin_addr);
        //2.bind
        bind(s_fd,(struct sockaddr *)&s_addr,sizeof(struct sockaddr_in));

        //3.listen
        listen(s_fd,10);

        int clen = sizeof(struct sockaddr_in);
        //4.accept
        while(1){
                c_fd = accept(s_fd,(struct sockaddr *)&c_addr,&clen);
                if(c_fd == -1){
                        perror("accept");
                }
                printf("get connect:%s\n",inet_ntoa(c_addr.sin_addr));if(fork()==0){
                        if(fork()==0){
                        while(1){
                                memset(msg,0,sizeof(msg));
                                printf("input:");
                                gets(msg);
                                write(c_fd,msg,strlen(msg));
                        }
                }

                                //5.read
                                while(1){
                                memset(readBuf,0,sizeof(readBuf));
                                n_read = read(c_fd,readBuf,128);
                                if(n_read == -1){
                                        perror("read");
                                }else{
                                        printf("get message :%d,%s\n",n_read,readBuf);
                                }
                                }
                                break;
                }
        }
        return 0;
}

客户端代码

#include<stdio.h>
#include<stdlib.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<string.h>
#include<unistd.h>

int main(int argc,char **argv)
{
        int c_fd;
        int n_read;
        char readBuf[128]={0};
        //char *msg = "message from client\n";
        char msg[128]={0};

        struct sockaddr_in c_addr;

        if(argc !=3){
                printf("param is not good\n");
                exit(-1);
        }

        memset(&c_addr,0,sizeof(struct sockaddr_in)); //1.socket
        c_fd = socket(AF_INET,SOCK_STREAM,0);
        if(c_fd == -1){
                perror("socket");
                exit(-1);
        }
        c_addr.sin_family = AF_INET;
        c_addr.sin_port = htons(atoi(argv[2]));
        inet_aton(argv[1],&c_addr.sin_addr);

        //2. connect
        if(connect(c_fd,(struct sockaddr *)&c_addr,sizeof(struct sockaddr))==-1){
                perror("connect");
                exit(-1);

        }
        while(1){
                if(fork()==0){
                        while(1){
                        memset(msg,0,sizeof(msg));
                        printf("input:");
                        gets(msg);
                        //3.send
                        write(c_fd,msg,strlen(msg)); }
                }
                while(1){
                memset(readBuf,0,sizeof(readBuf));
                n_read = read(c_fd,readBuf,128);
                if(n_read==-1){
                        perror("read");
                }else{
                        printf("get message from server:%d,%s\n",n_read,readBuf);
                }
                }

        }

        return 0;
}