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POServer not able to receive message from client
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15836362
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2013-04-05T14:21:48.160
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2013-04-05T15:23:55.817
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I am using Ubuntu 12.05.I have been trying to implement Stop and wait protocol through C socket programming.I have created two programs,one featuring the server and other one the client. Expected working of the code is explained through comments serversocket.c <pre><code> #include <sys/socket.h> #include <stdio.h> #include <stdlib.h> #include <netinet/in.h> #include <arpa/inet.h> #include <unistd.h> #include <error.h> #include <string.h> #include <sys/types.h> #include <time.h> int main(int argc,char *argv[]) { int listenfd = 0,qlength=10,connfd = 0,t=5; int n; struct sockaddr_in serv; struct sockaddr_in dest; socklen_t socksize = sizeof(struct sockaddr_in); char sendBuff[1024]="hi\n"; //time_t ticks; listenfd = socket(AF_INET,SOCK_STREAM,0); //socket for listening to connection requests memset(&serv,'0',sizeof(serv)); serv.sin_family = AF_INET; serv.sin_addr.s_addr = htonl(INADDR_ANY); serv.sin_port=htons(5000); bind(listenfd,(struct sockaddr *)&serv,sizeof(serv)); //binding the socket to a port listen(listenfd,2); connfd=accept(listenfd,(struct sockaddr *)&dest,&socksize); //another socket for sending and receiving on the previously built socket while(connfd){ printf("Incoming connection from %s-sending a hi...\n",inet_ntoa(dest.sin_addr)); send(connfd,sendBuff,strlen(sendBuff),0); //at first my server sends a hi sleep(3); n=recv(connfd,sendBuff,1024,0); //if hi received by the client,then server should receive "Message Received" from the client sendBuff[n]='\0'; printf("%s",sendBuff); connfd=accept(listenfd,(struct sockaddr *)&dest,&socksize); } return 0; } </code></pre> clientsocket.c <pre><code>#include <sys/socket.h> #include <sys/types.h> #include <netinet/in.h> #include <netdb.h> #include <stdio.h> #include <string.h> #include <stdlib.h> #include <unistd.h> #include <errno.h> #include <arpa/inet.h> int main(int argc, char *argv[]) { int sockfd = 0, n = 0,m=2; char recvBuff[1024]; struct sockaddr_in serv_addr; if(argc != 2) { printf("\n Usage: %s <ip of server> \n",argv[0]); return 1; } memset(recvBuff, '0',sizeof(recvBuff)); if((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) { printf("\n Error : Could not create socket \n"); return 1; } memset(&serv_addr, '0', sizeof(serv_addr)); serv_addr.sin_family = AF_INET; serv_addr.sin_port = htons(5000); if(inet_pton(AF_INET, argv[1], &serv_addr.sin_addr)<=0) { printf("\n inet_pton error occured\n"); return 1; } if( connect(sockfd, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0) { printf("\n Error : Connect Failed \n"); return 1; } while(m--){ //m is 2 initially,I want that sending and receiving should be done 2 times n = recv(sockfd,recvBuff,1024,0); recvBuff[n]='\0'; //"hi" is received printf("%s",recvBuff); if(recvBuff=="hi\n") send(sockfd,"Message Received",strlen("Message Received\n"),0);} //sending "Message received" return 0; } </code></pre> Now sending messages from server to client works fine, but client to server(Message received) is creating problems.Neither it is giving an error, nor correct results,it just gives a blank screen. 
Tags
<c><sockets><unix><client-server>
Title
Server not able to receive message from client
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1. USAkshay Jindal
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 POServer not able to receive message from client
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 USParker Kemp
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 POServer not able to receive message from client
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1. CODid you try and use a debugger to step through your program? Also, tweak your compiler to give you all the warnings possible. Treat each warning as an error and remove them all.
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 POServer not able to receive message from client
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 USAnish Ramaswamy

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