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Top Forums Programming Problem with Pipes => Only works first pipe Post 302535471 by serpens11 on Thursday 30th of June 2011 08:43:09 PM
Old 06-30-2011
Problem with Pipes => Only works first pipe

Hi!

I'm having problems with pipes... I need comunnications with childs processes and parents, but only one child can comunnicate with parent (first child), others childs can't.

A brief of code:

Code:
if(pipe(client1r)<0){
                perror("pipe");
        }
        if(pipe(client2r)<0){
                perror("pipe");
        }
        if(pipe(client3r)){
                perror("pipe");
        }
        listen(sock,5);
        while(1){
                FD_ZERO(&fds);
                FD_SET(client1r[0],&fds);
                FD_SET(client2r[0],&fds);
                FD_SET(client3r[0],&fds);
                FD_SET(sock,&fds);
                a=select(256,&fds,NULL,NULL,NULL);
                if(a>0){
                        c=0;
                        if(FD_ISSET(client1r[0],&fds)){
                                write(1,"test",12);
                        }
                        if(FD_ISSET(client3r[0],&fds)){
                                 write(1,"test",12);
                        }
                        if(FD_ISSET(client2r[0],&fds)){
                                write(1,"You Win",7);
                        }
                        if(FD_ISSET(sock,&fds)){
                                fd_client = accept(sock,0,0);
                                if(fd_client == -1){
                                        perror("accept");
                                }else{
                                        (*numlogin)=(*numlogin)+1;
                                        fill=fork();
                                        switch(fill){
                                            case 0:
                                                        if((*numlogin)==2){
                                                                close(client2r[0]);  
                                                                Client(fd_client,logins,shmid1,shmid2,shmid3,client2r[1]);
                                                        }
                                                        if((*numlogin)==1){
                                                                close(client1r[0]);
                                                               Client(fd_client,logins,shmid1,shmid2,shmid3,client1r[1]);
                                                        }
                                                        if((*numlogin)==3){
                                                                close(client3r[0]); 
                                                               Client(fd_client,logins,shmid1,shmid2,shmid3,client3r[1]);
                                                        }
                                                        break;
                                                case -1:
                                                        write(1,"Error al fork\n",14);
                                                        break;
                                                default:
                                                        close(client1r[1]);
                                                        close(client2r[1]);
                                                        close(client3r[1]);
                                                        close(fd_client); //No ho necessita
                                                        break; //PARE

Results are:

First pipe (client1r) works correctly, but others pipe (client2r and client3r) doesn't works. I don't understant why doesn't works, because others pipes are exactly the same, and then I call another function (function client) passin the value.

Any idea?

Thanks
 

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