这篇“Linux下select异步通讯怎么实现”文章的知识点大部分人都不太理解，所以小编给大家总结了以下内容，内容详细，步骤清晰，具有一定的借鉴价值，希望大家阅读完这篇文章能有所收获，下面我们一起来看看这篇“Linux下select异步通讯怎么实现”文章吧。
1.服务器端
/*select_server.c 2011.9.2 by yyg*/
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include#define MAXBUF 1024
int main(int argc,char **argv){
int sockfd,new_fd;
socklen_t len;
struct sockaddr_in my_addr,their_addr;
unsigned int myport,lisnum;
char buf[MAXBUF+1];
fd_set rfds;
struct timeval（argv[1]){
myport = atoi(argv[1]);
}
else
myport = 7838;if(argv[2]){
lisnum = atoi(argv[2]);
}
else
lisnum =2;
if((sockfd = socket(PF_INET,SOCK_STREAM,0))== -1){
perror("socket");
exit(1);
}bzero(&my_addr,sizeof(my_addr));
my_addr.sin_family = PF_INET;
my_addr.sin_port = htons(myport);
if(argv[3])
my_addr.sin_addr.s_addr = INADDR_ANY;
if(bind(sockfd,(struct sockaddr *)&my_addr,sizeof(struct sockaddr)) == -1){
perror("bind");
exit(1);
}
if(listen(sockfd, lisnum) == -1){
perror("listen");
exit(1);
}
while(1){
printf("\n----waiting for new connecting to start new char----\n");
len = sizeof(struct sockaddr);
if((new_fd = accept(sockfd,(struct sockaddr *)&their_addr,&len)) == -1){
perror("accept");
exit(errno);
}
else
printf("server:got connection from %s,port %d,socked %d\n",\
inet_ntoa(their_addr.sin_addr),\
ntohs(their_addr.sin_port),new_fd);
/*开始处理每个新连接上的数据收发*/
//printf("\n---ready to go.now you can chatting...input enter,then you can chat---\n");
while(1){
/*把集合清空*/
FD_ZERO(&rfds);
/*把标准输入句柄0加入到集合中*/
FD_SET(0,&rfds);
maxfd = 0;
/*把当前连接句柄new_fd加入到集合中*/
FD_SET(new_fd,&rfds);
if(new_fd > maxfd)
maxfd = new_fd;
/*设置最大等待时间*/
tv.tv_sec = 1;
tv.tv_usec = 0;retval = select(maxfd+1,&rfds,NULL,NULL,&tv);
if(retval == -1){
printf("select error!%s\n",strerror(errno));
break;
}
else if(retval == 0){
//printf("no message come,user no press the button,please wait...\n");
continue;
}
else{if(FD_ISSET(new_fd,&rfds)){
/*连接的socket 上有消息则接收并显示*/
bzero(buf,MAXBUF+1);
/*接收对方发过来的消息，最多MAXBUF字节*/
len = recv(new_fd, buf, MAXBUF, 0);
if(len > 0)
printf("recv msg success:%s! %d bytes rcv.\n ",buf,len);
else{
if(len 0)
printf("recv msg success:%s! %d bytes rcv.\n ",buffer,len);
else{
if(len
