How to chat using named pipe in UNIX?

#include<unistd.h>

#include<stdio.h>

#include<fcntl.h>

char string[]="patel";

int main(char argv[10][100],int argc)

{

        int fd;

        char buf[200];

        mknod("fifo",010777,0);

        if(argc == 2)

                fd=open("fifo",O_WRONLY);

        else

                fd=open("fifo",O_RDONLY);

        while(1)

        {

                if(argc==2)

                {       printf("writing");

                        write(fd,string,6);

                }

                else

                {

                        printf("Reading");

                        read(fd,buf,6);

                        printf("read string : %s ",buf);

                }

        }

}