Program 7):

AIM: Write C programs to illustrate the following IPC mechanisms:

a.     Pipes

b.     Fifos

c.      Message queues

d.     Shared memory

a)  PIPES

#include<stdio.h>

#include<stdlib.h>

#include<string.h>

#include<unistd.h>

int main()

{

int fd[2];

char data[100];

pid_t pid;

pipe(fd);

pid=fork();

if(pid==0)

{

close(fd[1]);

read(fd[0],data,100);

printf("Reading from pipe.....\n");

printf("%s",data);

}

else

{

close(fd[0]);

printf("Enter the string.....");

printf("\nWritng to pipe from parent...\n");

gets(data);

write(fd[1],data,100);

wait();

printf("\n");

}

return 0;

}

OUTPUT:

Reading from pipe….

Venky

Enter the string …..

Writing to pipe from parent…

b)  FIFO

      Sender

#includestdio.h

#includefcntl.h

#includesysstat.h

#includeunistd.h

int main()

{

int fd=0;

char data[100];

int len=0;

int i=1;

unlink(datapipe);

mkfifo(datapipe,0660);

fd=open(datapipe,O_RDONLY);

if(fd==-1)

{

printf(Error creating pipe);

return 1;

}

printf(receiver.c);

while(1)

{

len=read(fd,data,100);

if(len=0){break;}

data[len]='0';

printf(“\nstring %d!%s--” ,i,data);

i++;

}

close(fd);

unlink(datapipe);

printf(n);

return 0;

}

Receiver

#include<string.h>

#include<stdio.h>

#include<unistd.h>

#include<fcntl.h>

#include<sys/stat.h>

#include<stdlib.h>

int main()

{

int fd1=0;

char data[100];int len=0;

fd1=open("datapipe",O_WRONLY);

if(fd1==-1)

{

  printf("Error in accessing pipes:");

  exit(0);

}

while(1)

{

  len=read(0,data,100);

  if(len<=0)

     break;

  write(fd1,data,len);

}

  close(fd1);

  printf("\n");

return 0;

}

OUTPUT:

Receiver.c

String 1 venky