.. _Extended2Processes:

.. raw:: html

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.. avmetadata::
   :author: Michael S. Kirkpatrick
   :requires:
   :satisfies: Extended Example Processes
   :topic: Extended Example, Signal Handlers, Processes

Extended Example: Listing Files with Processes
==============================================

In this Extended Example, the main process starts by overwriting the ``SIGINT`` signal handler. The
process then enters a loop (line 29) where it repeatedly retrieves user input in the
``process_input()`` function. This function (lines 72 – 102) provides a simplified shell that
accepts two possible commands: ``ls`` and ``exit``. If the user enters the ``ls`` command, the main
process uses ``fork()`` and ``exec()`` to list files in the current directory (``list_files()`` in
lines 49 – 65), similar to how ``bash`` works. The ``exit`` command will terminate the program by
returning false from ``process_input()``. Finally, the overwritten ``SIGINT`` handler (lines 36 –
46) will also check for and ``kill()`` child processes that may have become stuck (e.g., if the
directory contains thousands of files).

.. codeinclude:: Processes/ExtEx-2.c
   :linenos: true