The system call fork() is used to create a new process in UNIX based operating systems and Linux systems. The fork() system call creates a child process when called from a parent process. Unix will make an exact copy of the parent's address space and give it
to the child. Therefore, the parent and child processes have separate
address spaces. Here is a C program which uses the fork() system call to create a process during execution. The program is commented well for better understanding.
Program
/*The program (parent process) reads an array from the user.
It sorts it in descending order.