Inter Process Communication Using Shared Memory

Coding:

#include<stdio.h>

#include<sys/shm.h>

#include<sys/ipc.h>

int main()

{

int child,shmid,i;

char *shmptr;

child=fork();

if(!child)

{

shmid=shmget(2041,32,0666|IPC_CREAT);

shmptr=shmat(shmid,0,0);

printf("\nPARENT WRITING");

for(i=0;i<10;i++)

{

shmptr[i]='a'+i;

putchar(shmptr[i]);

}

printf("\n\n%s",shmptr);

wait(NULL);

}

else

{

shmid=shmget(2041,32,0666);

shmptr=shmat(shmid,0,0);

printf("\n CHILD IS READING:");

for(i=0;i<10;i++)

putchar(shmptr[i]);

shmdt(NULL);

shmctl(shmid,IPC_RMID,NULL);

}

return 0;

}

Output:

 [telnet50@linux ~]$ ./a.out

PARENT   WRITING:

abcdefghij

 CHILD IS READING:

abcdefghij