The exact order of these consequences is unspecified.
All file descriptors open in the calling process are closed.
A zombie process is a process that only occupies a slot in the process table. It has no other space allocated either in user or kernel space. The parent process ID is set to 1 for all of the calling process's existing child processes and zombie processes. The controlling terminal associated with the session is disassociated from the session, allowing it to be acquired by a new controlling process.