The Linux C poll function uses

When learning about Linux concurrent non-blocking servers. See how you can use the poll function. Preliminary understanding and writing procedures were tested.

Server:

#include <unistd.h>#include<sys/types.h>/*Basic system data Types*/#include<sys/socket.h>/*Basic Socket Definitions*/#include<netinet/inch.h>/*sockaddr_in{} and other Internet Defns*/#include<arpa/inet.h>/*inet (3) Functions*/#include<poll.h>#include<stdlib.h>#include<errno.h>#include<stdio.h>#include<string.h>#defineMax_link 10intMain () {structsockaddr_in server_addr,client_addr; Bzero (&AMP;SERVER_ADDR,sizeof(SERVER_ADDR)); Server_addr.sin_family=af_inet; Server_addr.sin_addr.s_addr=htonl (Inaddr_any); Server_addr.sin_port= Htons (6888); socklen_t Socklen=sizeof(structsockaddr_in); intser_fd,con_fd; SER_FD=socket (Af_inet, Sock_stream,0); if(Bind (SER_FD, (structsockaddr*) &server_addr,sizeof(structsockaddr_in)) = =-1) {perror ("bind error"); Exit (-1); }    if(Listen (SER_FD,Ten) <0) {perror ("Listen error"); return-1; }        structPOLLFD Fds[max_link]; fds[0].fd=ser_fd; fds[0].events=Pollrdnorm; intI=1;  for(; i<max_link;i++) {FDS[I].FD=-1; Fds[i].events=Pollrdnorm; }        intReady_n; intLink_count=1; Charbuffer[1024x768];  while(1) {Ready_n=poll (fds,link_count,-1); if(ready_n==-1) {printf ("poll error \ n"); return 0; }        if(fds[0].revents &pollrdnorm) {            intCli=accept (SER_FD, (structsockaddr*) &client_addr, &Socklen);  for(i=1; i<max_link;i++){                if(fds[i].fd<0) {FDS[I].FD=CLI; printf ("new connect:%d \ t", i); printf ("%d\n", Link_count);  Break; }} Link_count++; Ready_n--; }         for(i=1; I<max_link && ready_n>0; i++){            if(Fds[i].fd >0){                if(Fds[i].revents &pollrdnorm) {                    intN=RECV (Fds[i].fd,buffer,1024x768,0); if(n==0) {FDS[I].FD=-1; Link_count--; }Else if(n>0) {Send (Fds[i].fd,buffer,n,0); } ready_n--; }            }                }                    }        return 0;}

Client:

#include <unistd.h>#include<sys/types.h>/*Basic system data Types*/#include<sys/socket.h>/*Basic Socket Definitions*/#include<netinet/inch.h>/*sockaddr_in{} and other Internet Defns*/#include<arpa/inet.h>/*inet (3) Functions*/#include<sys/Select.h>/*Select function*/#include<stdlib.h>#include<errno.h>#include<stdio.h>#include<string.h>#defineMAXLINE 10240#defineMax (a) (a) > (b)? (a): (b))//typedef struct SOCKADDR SA;voidHandleintsockfd);intMainintargcChar**argv) {    Char* Servinetaddr ="127.0.0.1"; intServport =6888; CharBuf[maxline]; intCONNFD; structsockaddr_in servaddr; if(ARGC = =2) {servinetaddr= argv[1]; }    if(ARGC = =3) {servinetaddr= argv[1]; Servport= Atoi (argv[2]); }    if(Argc >3) {printf ("usage:selectechoclient <IPaddress> <port>\n"); return-1; } CONNFD= Socket (Af_inet, Sock_stream,0); Bzero (&AMP;SERVADDR,sizeof(SERVADDR)); Servaddr.sin_family=af_inet; Servaddr.sin_port=htons (Servport); Inet_pton (Af_inet, SERVINETADDR,&servaddr.sin_addr); if(Connect (CONNFD,structSOCKADDR *) &servaddr,sizeof(SERVADDR)) <0) {perror ("Connect Error"); return-1; } printf ("Welcome to Selectechoclient\n");     Handle (CONNFD); /*Do it all*/Close (CONNFD); printf ("exit\n"); Exit (0);}voidHandleintCONNFD) {FILE* fp =stdin; CharSendline[maxline], recvline[maxline];    Fd_set RSet; Fd_zero (&RSet); intMaxfds = Max (Fileno (FP), CONNFD) +1; intnread;  for (;;) {Fd_set (Fileno (FP),&RSet); Fd_set (CONNFD,&RSet); if(Select(Maxfds, &rset, NULL, NULL, NULL) = =-1) {perror ("Select Error"); Continue; }        if(Fd_isset (CONNFD, &RSet)) {            //Receiving server ResponseNread =Read (CONNFD, recvline, MAXLINE); if(Nread = =0) {printf ("server close the connection\n");  Break; }             Else if(Nread = =-1) {perror ("Read Error");  Break; }            Else {                //Server ResponseWrite (Stdout_fileno, recvline, nread); }          }        if(Fd_isset (Fileno (FP), &RSet)) {            //Standard input readable            if(Fgets (Sendline, MAXLINE, fp) = =NULL) {                //EOF Exit                 Break; }             Else{Write (CONNFD, Sendline, strlen (Sendline)); }        }    } }

The Linux C poll function uses