fork() & Switch Case in C

[rahul_shilps]

My sw.c is as follows:

--------------------------------------------------------------

#include<stdio.h>

int main()
{
int pid;
pid = fork();

switch(pid)
{
case 0:
printf ("Am child, my ID: %d", getpid() );
printf ("Am child, my Parent id: %d",getppid() );
break;

case -1:
printf ("The child process has not created");
break;

default:
printf ("am in default , process id: %d",
getpid());
sleep(10);
break;
} // switch case closed

system("ps");
} // main function close

--------------------------------------------------------------

Now i think, neither parent should not execute the code inside the default block of the nor the child.

As we know, value of pid=0; so it should not execute default block! It should only execute the block with case 0. right.

When i look at the lines of code which i keep in bold & italic, these line return me same ID.

1) Why? How?

2) What is the fundamental concept behind a fork()?

3)What is the role & scope of the Parent process then?

please help. I will be thankful to you.

[coopstah13]

This sounds like a homework question.

[Cabhan]

I agree that this sounds like homework, so I won't answer you directly.

I think that you should go and research how the fork() function works. Go to your terminal and enter the command "man fork" to see a manual page that will explain everything. Hopefully this will help you understand.

[rahul_shilps]

ok, i will do it. i hope i will understand.
but if i get any difficulty then i'll be here again.

Thanks. I am new bee to tis Linux programming thats why i asked this question.