Chat Program

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1

i need chat program in c. know sockets to some extent.

2

i had the c program to transfer files. can anybody tell me the procedure to change it into chat program.

3

check out this link: Beej's Guides

4

hai friends,
the following is my code. i am not getting the right output. kindly help me.

#include <unistd.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <string.h>
#include <sys/socket.h>
#include <stdio.h>
#include <readline/readline.h>
#define max 4096
int main()
{
int cpid,sd,nsd,i,port=5200;
char fname[30],line[max];
struct sockaddr_in ser;
struct sockaddr_in cli;
ssize_t n;

if ((sd=socket(AF_INET,SOCK_STREAM,0))<0)
        {
        printf("\nError:Socket Creation");
        return 0;
        }
bzero((char*)&ser,sizeof(ser));
printf("\nPort Address is %d",port);
ser.sin_family=AF_INET;
ser.sin_port=htons(port);
ser.sin_addr.s_addr=htonl(INADDR_ANY);

if (bind(sd,(struct sockaddr*)&ser,sizeof(ser))<0)
        {
        printf("\nError:Binding");
        return 0;
        }
i=sizeof(cli);    
listen(sd,1);

printf("Server Module\n");

nsd=accept(sd,(sd,(struct sockaddr*)&cli),&i);
if (nsd==-1)
        {
        printf("\nError:Client accepts the problem");
        return 0;
        }
printf("Client Accepted");
printf("Start Chatting");

if (cpid=(fork()<0)) { // this is the child process
    close(sd); // child doesn't need the listener
    scanf("%s",line);
        if (send(nsd, line,sizeof(line), 0) == -1)
        printf("send");
    close(nsd);

}
if(cpid>0)
{
//receive the message steps
}
close(sd);

return 0;
}   

// client program
#include <stdio.h>
#include <unistd.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <string.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#define max 4096

int main()
{
int n,sd,nsd,i,port=5200;
char line[max],file[30];
struct sockaddr_in ser;
int childpid;
if ((sd=socket(AF_INET,SOCK_STREAM,0))<0)
        {
        printf("\nError:Socket Creation");
        return 0;
        }
bzero((char *)&ser,sizeof(ser));
printf("\nPort Address is %d",port);
ser.sin_family=AF_INET;
ser.sin_port=htons(port);
ser.sin_addr.s_addr=htonl(INADDR_ANY);
if (connect(sd,(struct sockaddr*)&ser,sizeof(ser))==-1)
        {
        printf("\nError:Binding");
        return 0;
        }
printf("Client Module");
printf("\nClient:");
if (fork()) { // this is the child process
    close(sd); // child doesn't need the listener
        if ((n=recv(sd, line, max, 0)) == -1) {
        printf("recv");
        exit(1);
    }

    line[n] = '\0';

    printf("Received: %s",line);
close(nsd);
}
close(sd);

return 0;
}
5

how to read strings and send it to server or to client. actually in my chat program, iam gng to use fork(). using child process i'm gng to send the message and using parent process i'm gng to receive the message. hw i can do.