Subj : named pipe problem on linux
To   : comp.lang.c++,comp.os.linux
From : richard
Date : Mon Nov 01 2004 05:36 am

I have a simple test to pass information from a client to a server 
using named pipe. what I really want is: when I type a line on the client,
the server will output the line immediately. but to my surprise, I always 
have to terminate the client to get the server in action, i.e. prints out
what I typed.

anything I missed? I am compiling using gcc without any option.

thanks,
---RICH

---------------------
server
---------------------
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <unistd.h>
 
#include <linux/stat.h>
 
#define FIFO_FILE       "MYFIFO"
 
int main(void)
{
        FILE *fp;
        char readbuf[80];
 
        /* Create the FIFO if it does not exist */
        umask(0);
        mknod(FIFO_FILE, S_IFIFO|0666, 0);
 
        while(1)
        {
                fp = fopen(FIFO_FILE, "r");
                fgets(readbuf, 10, fp);
                printf("Received string: %s\n", readbuf);
                fclose(fp);
        }
 
        return(0);
}

-------
client
-------
#include <stdio.h>
#include <stdlib.h>
 
#define FIFO_FILE       "MYFIFO"
 
int main(int argc, char *argv[])
{
        FILE *fp;
 
                char str[20];
 
        if((fp = fopen(FIFO_FILE, "w")) == NULL) {
                perror("fopen");
                exit(1);
        }
 
                while( scanf("%s", str) != EOF  )
                {                       fputs(str, fp);
                                        fputs(str, stdout);
                }
 
        fclose(fp);
        return(0);
}

.