- 其代码如下
#include <stdio.h> #include<stdlib.h> #include<sys/socket.h> #include<unistd.h> #define SERV_PORT 9898 #define SERV_IP "127.0.0.1" #include<ctype.h> #include<arpa/inet.h> int main() { int lfd,cfd,n,i; char buf[BUFSIZ]; struct sockaddr_in serv_addr,client_addr; socklen_t client_addr_len; lfd=socket(AF_INET,SOCK_STREAM,0);// serv_addr.sin_family=AF_INET; serv_addr.sin_port=htons(SERV_PORT); serv_addr.sin_addr.s_addr=htonl(INADDR_ANY);// bind(lfd,(struct sockaddr*)&serv_addr,sizeof(serv_addr)); listen(lfd,128);//128 is uplimit client_addr_len=sizeof(client_addr); cfd=accept(lfd,(struct client_addr*)&client_addr,&client_addr_len);//will recv fd and return fd while(1) { n=read(cfd,buf,sizeof(buf)); for(i=0;i<n;i++) { buf[i]=toupper(buf[i]); } write(cfd,buf,n); } printf("Hello World!\n"); return 0; }
测试:打开一个终端输入 nc 127.0.0.1 9898