Would it be possible for the user to develop a new command interpreter using the system call interface provided by the operating system?
It reads commands from the user or from a file of commands and
executes them, usually by turning them into one or more system
calls. It is usually not part of the kernel since the command
interpreter is subject to changes. An user should be able to
develop a new command interpreter using the system-call interface
provided by the operating system. The command interpreter allows an
user to create and manage processes and also determine ways by
which they communicate (such as through pipes and files). As all of
this functionality could be accessed by an user-level program using
the system calls, so it should be possible for the user to develop
a new command-line interpreter.