The Concept of Fork
The Unix system call for process creation is called fork().
The fork system call creates a child process that is a clone of the parent.
- Child has a (virtual) copy of the parent’s virtual memory.
- Child is running the same program as the parent.
- Child inherits open file descriptors from the parent.
(Parent and child file descriptors point to a common entry in the system open file table.)
- Child begins life with the same register values as parent.
The child process may execute a different program in its context with a separate exec() system call.