unix-poll

ulimit -n xxx //修改文件描述符个数

#include<stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include<iostream>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include<sys/select.h>
#include<errno.h>
#include<sys/poll.h>
#include<sys/signal.h>
using namespace std;
void handler(int sig){
     cout<<sig<<endl;
}
int main()
{   signal(SIGPIPE,SIG_IGN);
    //signal(SIGPIPE,handler);
    int sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd == -1)
    {
        perror("socket() err");
        return -1;
    }
    int on = 1;
    if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1)
    {
        perror("setsockopt() err");
        return -1;
    }
    char recvbuf[1024];
    int conn;
    struct pollfd client[2048];
    for(int i=0;i<2048;i++){
        client[i].fd=-1;
    }
    struct sockaddr_in addr;
    addr.sin_family = AF_INET;
    addr.sin_port = htons(8888);
    addr.sin_addr.s_addr = inet_addr("127.0.0.1");
    if (bind(sockfd, (struct sockaddr *) &addr, sizeof(addr)) == -1)
    {
        perror("bind() err");
        return -1;
    }
    if (listen(sockfd, SOMAXCONN) == -1)
    {
        perror("bind() err");
        return -1;
    }
    struct sockaddr_in peeraddr;
   int nready;
   client[0].fd=sockfd;//设置监听位
   client[0].events=POLLIN;//设置我们感兴趣的事件为读取事件
   int maxi=0;
   while(1){
       int i;
       nready=poll(client,maxi+1,-1);
       if(client[0].revents&POLLIN){
           socklen_t peerlen = sizeof(peeraddr);
           conn=accept(sockfd,(struct sockaddr *) &peeraddr, &peerlen);
           printf("ip=%s port=%d\n",inet_ntoa(peeraddr.sin_addr),ntohs(peeraddr.sin_port));
       for( i=0;i<2048;i++){
           if(client[i].fd<0){
               client[i].fd=conn;
               if(i>maxi)
                   maxi=i;
               break;
           }
       }
         client[i].events=POLLIN;//将conn的事件也设为POLLIN
       
              if(--nready<=0)
                  continue;
   }
       for(int i=1;i<=maxi;i++){
           conn=client[i].fd;
           if(conn==-1)
               continue;
           if(client[i].events&POLLIN){
               int rc = read(conn, recvbuf, sizeof(recvbuf));
if (rc == 0)
{   
    cout<<"client has closed"<<endl;
   client[i].fd=-1;
    close(conn);  

}
           else{ 
               printf("recv message:%s\n", recvbuf);
            write(conn, recvbuf, rc);
            memset(recvbuf, 0, sizeof(recvbuf));
            
           
            if(--nready<=0)
               break;
       }
   
   }
}
}
    close(conn);
    close(sockfd);
    return 0;
}

ulimit -n 2048