比较进程和多线程TCP网络编程套接字

比较网络程序的优缺点：

多进程：

缺点：

1.链接来后才创建子进程，性能受损

2.进程消耗资源，只能受理有限个服务

3.调度压力增大，影响性能

优点：

1.处理多个任务

2.编写周期短

3.独立性、稳定性强

多进程（共享文件描述符）：

缺点：

1.链接来后才创建子进程，性能受损

2.进程消耗资源，只能受理有限个服务

3.调度压力增大，影响性能

优点：

1.处理多个任务

2.编写周期短

3.独立性、稳定性强 但有可能由于线程安全问题挂掉

以下是多线程网络程序

//服务器

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


#define MAX 128

typedef struct 
{
    int sock;
    char ip[24];
    int port;
}net_info_t;



void service(int sock,char* ip,int port)
{
    char buf[MAX];
    while(1)
    {
        buf[0] = 0;
        ssize_t s =  read(sock,buf,sizeof(buf)-1);
        if(s > 0)
        {
            buf[s] = 0;
            printf("[%s:%d] say# %s\n",ip,port,buf);
            write(sock,buf,strlen(buf));
        }
        else if(s == 0)
        {
            printf("client [%s:%d] quit\n",ip,port);
            break;
        }
        else
        {
            printf("read error\n");
            break;
        }
    }
}

int statup(char* ip,int port)
{
    int sock = socket(AF_INET,SOCK_STREAM,0);
    if(sock < 0)
    {
        printf("socket error\n");
        exit(2);
    }
    struct sockaddr_in local;
    local.sin_family = AF_INET;
    local.sin_addr.s_addr = inet_addr(ip);
    local.sin_port = htons(port);

    if(bind(sock,(struct sockaddr*)&local,sizeof(local)) < 0)
    {
        printf("bind error\n");
        exit(3);
    }

    if(listen(sock,5) < 0)
    {
        printf("listen error\n");
        exit(4);
    }
    return sock;
}

void *thread_service(void* arg)
{
    net_info_t *p = (net_info_t*)arg;
    service(p->sock,p->ip,p->port);
    close(p->sock);

    free(p);
}

// ./tcpServer 127.0.0.1 8080
int main(int argc,char* argv[])
{
    if(argc != 3)
    {
        printf("Usage: %s[ip][port]\n",argv[0]);
        return 1;
    }
    int listen_sock = statup(argv[1],atoi(argv[2]));

    struct sockaddr_in peer;

    char ipBuf[24];
    for(;;)
    {
        ipBuf[0] = 0;
        socklen_t len = sizeof(peer);
        int new_sock = accept(listen_sock,(struct sockaddr*)&peer,&len);
        if(new_sock < 0)
        {
            printf("accept error\n");
            continue; 
        }
        inet_ntop(AF_INET,(const char*)&peer.sin_addr,ipBuf,sizeof(ipBuf));
        int port = ntohs(peer.sin_port);
        printf("get a new connet,[%s:%d]\n",ipBuf,port);
        
        net_info_t *info = (net_info_t*)malloc(sizeof(net_info_t));
        if(info == NULL)
        {
            perror("malloc");
            close(new_sock);
            continue;
        }
        info->sock = new_sock;
        strcpy(info->ip,ipBuf);
        info->port = port;
        pthread_t tid;
        pthread_create(&tid,NULL,thread_service,(void*)info);
        
        pthread_detach(tid);//线程分离
        
        //service(new_sock,ipBuf,port);
        //close(new_sock);
    }

    return 0;
}

//客户端

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


#define MAX 128


// ./tcpClient 127.0.0.1 8080
int main(int argc,char* argv[])
{
    if(argc != 3)
    {
        printf("Usage: %s [ip] [port]\n",argv[0]);
        exit(1);
    }
    int sock = socket(AF_INET,SOCK_STREAM,0);
    if(sock < 0)
    {
        printf("socket error\n");
        exit(2);
    }

    struct sockaddr_in server;
    server.sin_family = AF_INET;
    server.sin_port = htons(atoi(argv[2]));
    server.sin_addr.s_addr = inet_addr(argv[1]);
    if(connect(sock,(struct sockaddr*)&server,sizeof(server)) < 0)
    {
        printf("connect error\n");
        exit(3);
    }
   
    char buf[MAX];

    while(1)
    {
        printf("please Enter# ");
        fflush(stdout);
        ssize_t s = read(0,buf,sizeof(buf)-1);
        if(s > 0)
        {
            buf[s-1] = 0;
            if(strcmp("quit",buf) == 0)
            {
                printf("client quit\n");
                break;
            }
            write(sock,buf,strlen(buf));
            s = read(sock,buf,sizeof(buf)-1);
            buf[s] = 0;
            printf("Server Echo %s\n",buf);
        }
        
    }
    close(sock);
    return 0;
}

[root@localhost consumer]# netstat -nlpt
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name    
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN      1/systemd           
tcp        0      0 127.0.0.1:8080          0.0.0.0:*               LISTEN      8964/./tcpServer