What happens to child process once the shell command is completed? [migrated]

So i am using exec to open a shell and run a shell command for me which is:

exec(‘del filename & exit’)

Using exit to close the Shell

I have to use this exec multiple times in a single run, i have not been able to find what happens to the child process once it goes to exit and closes the CMD, does the child process close itself as soon as the command is completed or do i have to explicitly close the child process