======
 MyLs
======

Deadline: October 3rd, 2014

.. sectnum::

Instructions
============

Implement a program named ``myls`` that matches the following
documentation::

   Usage: myls [OPTION]... [FILE]...

   List information about the FILEs (the current directory
   by default). Sort the output alphabetically by default.

   Options:
     -R       Recurse into subdirectories.
     -l       Use a long listing format.

- The program must terminate with code 0 if the operation
  completes successfully, 1 otherwise.
- Use only one column for the output.
- Entries whose name start with a period (``.``) must be omitted,
  except if explicitly given on the command line.
- For the long listing, use the following format: file mode, number of
  links, owner user ID, group ID, number of bytes in the file,
  datetime of last modification in format YYYY-MM-DD HH:MM:SS,
  entry name, optionally followed by “``->``” and the link target
  for symbolic links.
- You may use any standard C function (either from ISO C 1999/2011 or
  POSIX).
- You may not use ``system`` or any other mechanism that invokes an
  external program.

You may implement the following for a higher grade:

- multi-column output if the output is a terminal;
- output sorting: by default alphanumeric on the entry name;
  no sorting if ``-f`` is specified; by modification time if ``-t`` is specified,
  by size if ``-S`` is specified. Tip: use ``qsort(3)``;
- any extra feature you deem particularly useful.

Grading
=======

- 4 points if ``myls`` works without arguments or with only one file/directory argument.
- +1 point if ``-R`` is properly implemented.
- +1 point if ``-l`` is properly implemented.
- +1 point if ``myls`` also supports more than 1 file/directory argument.
- +0.5 point if multi-column output is properly implemented.
- +1.5 point if output sorting is properly implemented (including ``-f``, ``-t`` and ``-S``);
- +1 point if any additional feature is implemented and duly documented in an enclosed ``README`` file, and your examinator agrees it is indeed useful.

----

Copyright and licensing
=======================

Copyright © 2014, Raphael ‘kena’ Poss.  Permission is granted to
distribute, reuse and modify this document and other documents for the
Systems Programming course by the same author according to the terms
of the Creative Commons Attribution-ShareAlike 4.0 International
License.  To view a copy of this license, visit
`http://creativecommons.org/licenses/by-sa/4.0/
<http://creativecommons.org/licenses/by-sa/4.0/>`_.