How to Create a new Process on Ubuntu, Debian, Arch Linux

A Linux process is an instance of a program that is being executed by the Linux kernel. When a program is executed on a Linux system, the kernel creates a new process to run the program. The process is responsible for executing the program's instructions and managing its resources, such as memory and input/output operations.

There are several reasons why you might want to create a new Linux process. For example, you might want to run multiple instances of the same program concurrently, or you might want to run a program that performs a specific task in the background while you continue to use your system for other tasks.

Creating a new process allows you to run multiple programs or multiple instances of the same program simultaneously, which can be useful in a variety of situations.

Programmatically Creating a new Process on Linux Systems:

To create a new process on Linux, you can use the fork() system call. The fork() system call creates a new process by duplicating the current process. The new process, known as the child process, is an exact copy of the original process, known as the parent process.

The fork() system call returns a value of 0 to the child process and a positive value, which is the PID of the child process, to the parent process. This allows the child and parent processes to determine which process they are, and to take appropriate action accordingly.

Here is an example of how the fork() system call can be used to create a new process:

#include <unistd.h>
#include <sys/types.h>
#include <stdio.h>
int main(){
    pid_t pid;
    /* Create a new process */
    pid = fork();
    if (pid == 0)
    {
        /* This is the child process */
        printf("I am the child process\n");
    }
    else
    {
        /* This is the parent process */
        printf("I am the parent process, my child's PID is %d\n", pid);
    }
    return 0;
}

In this example, the fork() system call is used to create a new child process. The child process prints a message indicating that it is the child process, while the parent process prints a message indicating that it is the parent process and the PID of the child process.

Keep in mind that the fork() system call creates a new process by duplicating the current process, which can be resource-intensive. It is generally recommended to use other methods, such as the exec() family of functions, to create new processes in a more efficient manner.

Summary:

Overall, creating a new Linux process allows you to run multiple programs or multiple instances of the same program concurrently, and to isolate programs from the rest of the system for improved stability and performance. The fork() system call is essential to create them. And once you have created a process, it is very easy to kill it as well.