Question

Write a program that creates two child processes, child1 should write down the pipe and child2 that reads from the pipe. Make the reading process print any messages it receives on its standard output (the screen).                         

Answer 1

/*Program in c*/

#include<stdio.h>
#include<unistd.h>

int main() {
   int pipefds[2],i;
   int status_of_return;

   char msgWrite[2][20]={"SRTTC", "INDIA"};
   char msgRead[20];
   status_of_return= pipe(pipefds);
   if (status_of_return== -1) {
      printf("Unable to create pipe\n");
      return 1;
   }
   int fl=0;

     
   int pid2 = fork();// child 2
   int pid1 = fork();//child 1


   // Child 1 process
   if (pid1 == 0 && pid2 > 0) {
      read(pipefds[0], msgRead, sizeof(msgRead));//reading message from pipe
      printf("Child 2 Process - Reading from pipe – Message 1 is %s\n", msgRead);
      read(pipefds[0], msgRead, sizeof(msgRead));//reading message from pipe
      printf("Child 2 Process - Reading from pipe – Message 2 is %s\n", msgRead);
   
   } else if( pid2 == 0 && pid1 > 0 ){ //Child process
      printf("Child 1 Process - Writing to pipe - Message 1 is %s\n", msgWrite[0]);
      write(pipefds[1], msgWrite[0], sizeof(msgWrite[0]));//write message to pipe
      printf("Child 1 Process - Writing to pipe - Message 2 is %s\n", msgWrite[1]);
      write(pipefds[1], msgWrite[1], sizeof(msgWrite[1]));//write message to pipe
   }
   else{
       //printf("Parent Process executed, Run Again");
   }

   return 0;
}

/*

output

Child 1 Process - Writing to pipe - Message 1 is SRTTC
Child 1 Process - Writing to pipe - Message 2 is INDIA
Child 2 Process - Reading from pipe – Message 1 is SRTTC
Child 2 Process - Reading from pipe – Message 2 is INDIA

*/