Why process forking?

If a a child process is forked from parent process, whenever child process crashes, linux will notify the parent process through events. For this parent process has to register a callback with linux, so that linux will call the callback with events.

When forking happens a child process is created which is an exact replica of parent process even with same register contents. Both processes continue to execute individually. For forking parent would have just executed fork() call. Upon execution parent will receive child process id as fork() return value. Child will get null as fork() return value.

Fork also has another advantage. We can share common data between both processes. Linux allows this.