IMPLEMENTATION OF LINUX SYSTEM CALLS

AIM:

To write a C program using LINUX system calls (fork(),wait(),getpid()).

ALGORITHM:

Step1: Start the process.

Step2: Create a new process (parent process) using fork() system call.

Step3: Create a identical copy of parent process(child process) using fork () system call

Step4: Process id is created for both child and parent process using getpid() system call

Step5: The Child process is made to execute.

Step6: After the exiting of the child process parent process will get exit

Step7: Stop the process.

PROGRAM:

#include<stdio.h>

#include<sys/types.h>

#include<sys/wait.h>

#include<unistd.h>

void parent ();

void child();

main ()

{

int r;

r=fork();

{

printf(“fork empty”);

}

if(r>0)

parent(r);

else

child(r);

}

void child()

{

int i;

printf(“child starts executing”);

for(i=0;i<5;i++)

{

printf(“\n child %d is executing %d time”,getpid(),i);

sleep(i);

}

printf(“child %d exit \n”,getpid());

}

void parent(pid_t child_pid)

{

printf(“\n Parent %d watiting for child %d to start the executing “, getpid(),child_pid);

printf(“\n”);

waitpid(child_pid,NULL,0);

printf(“Parent %d exit \n”,getpid());

}

OUTPUT:

Parent 269 watiting for child 70 to start the executing

Child starts executing

Child 270 is executing 0 time

Child 270 is executing 1 time

Child 270 is executing 2 time

Child 270 is executing 3 time

Child 270 is executing 4 time

Child 270 exit.

Parent 269 exit

RESULT:

 Thus the given C Program is executed and output is verified.