select in socket
来源:互联网 发布:mac 火鹤色 编辑:程序博客网 时间:2024/06/04 20:02
/* server.c */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netinet/in.h>
#define MAXLINE 80
#define SERV_PORT 8000
int main(int argc, char **argv)
{
int i, maxi, maxfd, listenfd, connfd, sockfd;
int nready, client[FD_SETSIZE];
ssize_t n;
fd_set rset, allset;
char buf[MAXLINE];
char str[INET_ADDRSTRLEN];
socklen_t cliaddr_len;
struct sockaddr_in cliaddr, servaddr;
listenfd = socket(AF_INET, SOCK_STREAM, 0);
bzero(&servaddr, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
servaddr.sin_port = htons(SERV_PORT);
bind(listenfd, (struct sockaddr *)&servaddr, sizeof(servaddr));
listen(listenfd, 20);
maxfd = listenfd; /* initialize */
maxi = -1; /* index into client[] array */
for (i = 0; i < FD_SETSIZE; i++)
client[i] = -1; /* -1 indicates available entry */
FD_ZERO(&allset);
FD_SET(listenfd, &allset);
for ( ; ; ) {
rset = allset; /* structure assignment */
nready = select(maxfd+1, &rset, NULL, NULL, NULL);
if (nready < 0) {
perror("select error");
exit(-1);
}
if (FD_ISSET(listenfd, &rset)) { /* new client connection */
cliaddr_len = sizeof(cliaddr);
connfd = accept(listenfd, (struct sockaddr *)&cliaddr, &cliaddr_len);
printf("received from %s at PORT %d\n",
inet_ntop(AF_INET, &cliaddr.sin_addr, str, sizeof(str)),
ntohs(cliaddr.sin_port));
for (i = 0; i < FD_SETSIZE; i++)
if (client[i] < 0) {
client[i] = connfd; /* save descriptor */
break;
}
if (i == FD_SETSIZE) {
fputs("too many clients\n", stderr);
exit(1);
}
FD_SET(connfd, &allset); /* add new descriptor to set */
if (connfd > maxfd)
maxfd = connfd; /* for select */
if (i > maxi)
maxi = i; /* max index in client[] array */
if (--nready == 0)
continue; /* no more readable descriptors */
}
for (i = 0; i <= maxi; i++) { /* check all clients for data */
if ( (sockfd = client[i]) < 0)
continue;
if (FD_ISSET(sockfd, &rset)) {
if ( (n = read(sockfd, buf, MAXLINE)) == 0) {
/* connection closed by client */
close(sockfd);
FD_CLR(sockfd, &allset);
client[i] = -1;
} else {
int j;
for (j = 0; j < n; j++)
buf[j] = toupper(buf[j]);
write(sockfd, buf, n);
}
if (--nready == 0)
break; /* no more readable descriptors */
}
}
}
}
结果 打印:
received from 127.0.0.1 at PORT 60539
就一直在跑。 将客户端发的再返回给客户端。
- select in socket
- TCP socket, select model in linux.
- TCP socket, select model in linux
- socket select
- Socket Select
- Socket & Select
- Socket-Select
- Socket Select
- socket select
- socket --- select()
- socket select
- socket select
- select socket
- SELECT IN
- Select in 与 Select any
- socket select代码
- socket select()用法
- Socket select的用法
- example:利用impdp通过dblink导入数据库
- 腾讯微博开放平台
- geotools学习1从postgressql取shp并且展示(java postgis)
- 学习使用SQLite(版本3.7.4)(中D)
- 使用GeoTools 2.3M连接到POSTGIS数据库
- select in socket
- 一段代码,演示GeoTools筛选器的用法
- 网页dangdang
- 设计师需要的知识体系
- ASP.NET中用IHttpModule接口实现伪静态
- rm和rmdir 删除目录
- HTTP_X_FORWARDED_FOR 和 REMOTE_ADDR
- linux进程状态分析
- HDU 4258 Covered Walkway (DP +数形结合)#by Plato 终于A出来了~~~~~