Fork System Call in Linux


Write a C program to do the following when executed on a Linux system.

1. The parent process creates two other processes (child processes).

2. The parent prints "PARENT"

3. One child prints "CHILD 1"

4. The other child prints "CHILD 2"



C Code:

#include <stdio.h>

#include <unistd.h>



int main()

{

     if (fork())

  {

     printf("parent\n");

     if(fork()==0)

   {

     printf("child1\n");

   }

  }

     else

  {

     printf("child2\n");

  }

     return 0;

}

Comments

Post a Comment

Popular posts from this blog

Programming Using GNU Octave

Image
  Questions: 1 A small object is projected from a toy gun to travel some distance and land on the ground. 1. Write a function to model the dynamics of the object in Octave called f_trajectory. f_trajectory will accept following arguments in the same order (measured in the given units). Also specify the default values for each parameter as given in brackets. i. h(5) : Initial height of the projectile (m) ii. g(9.81) : acceleration from gravity (m/s/s) iii. v(25) : speed at initial release (m/s) iv. theta(π/4) : angle of release (radians) v. t : a vector representing the points in time For default values of t check if the variable ‘exist’ with name ‘t’ and type ‘var’ if not initialize it as a row vector starting from 0 and goes to 5 with increments of 0.1. If x is distance and y is height, the equations below describe their dependence on time and all the other parameters. 𝑥(𝑡)=𝑣𝑐𝑜𝑠(𝜃)𝑡 ----------------(eq1) 𝑦(𝑡)=ℎ+𝑣𝑠𝑖𝑛(𝜃)𝑡− 12𝑔𝑡2 ---------------(eq2) Convert the above e
Read more

Library Problem

Image
A giant library has just been inaugurated this week. It can be modeled as a sequence of N consecutive shelves with each shelf having some number of books. No, think of the following two queries which can be performed on these shelves. ● Change the number of books in one of the shelves. ● Obtain the number of books on the shelf having the kth rank within the range of shelves. A shelf is said to have the kth rank if its position is k when the shelves are sorted based on the number of the books they contain, in ascending order. Can you write a program to simulate the above queries? Input Format : The first line contains a single integer T, denoting the number of test cases. The first line of each test case contains an integer N denoting the number of shelves in the library. The next line contains N space separated integers where the ith integer represents the number of books on the ith shelf where 1<=i<=N. The next line contains an integer Q denoting the number of queries to
Read more

What Is A Gamma Ray Burst?

Image
Imagine if you could gather the energy from every star within a hundred million light-years. From thousands of galaxies, each with billions of stars. Imagine, you could take this kind of power, and use it to fire the biggest super-weapon in the universe. Imagine the damage you could do. It turns out, you don't need to imagine it. These exist, and they're called gamma-ray bursts. But what are these cosmic snipers? And what happens if one takes a shot at Earth? To understand gamma-ray bursts, we first have to understand gamma rays. Gamma rays are electromagnetic radiation – waves that carry energy just like visible light. Visible light is a tiny part of the electromagnetic spectrum: it's the part your eyes can see. At lower energies, there are radio waves, microwaves, and infrared. And at higher energies: ultraviolet, x-rays, and gamma rays. Gamma rays are incredibly powerful. A single gamma-ray photon is more energetic than a million visible photons combined. Their
Read more