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--- haas:spring2014:unix:projects:puzzle_box [2014/01/20 20:37] – created wedge
+++ haas:spring2014:unix:projects:puzzle_box [2014/02/02 15:44] (current) – [Procedure] wedge
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-coming soon
+<WRAP centeralign round box>
+<WRAP><color red><fs 200%>Corning Community College</fs></color></WRAP>
+<WRAP><fs 150%>CSCS1730 UNIX/Linux Fundamentals</fs></WRAP>
+</WRAP>
+~~TOC~~
+======Project: THE PUZZLEBOX======
+=====Objective=====
+To become familiar with another useful utility, and to develop some basic debugging/diagnostic abilities.
+=====Background=====
+The filetype of a file can be extremely important when determining what application is used to open it.
+Most of the time a file is named correctly, for instance a file ending in **.c** can be assumed to be the source code of a C program, or **.gz** to be a gzipped file.
+With the **dircolors**(**1**) utility colorizing specific files, it is further assuming that files which end in **.mpg** are really MPEG files and colors them accordingly, and the same for **.zip** files, etc.
+In other operating systems, a file's extension determines what application is used to open the particular file. If a file that ends in **.mp3** is really a **.png** file, the default MP3 player is going to have difficulties.
+Sometimes files are not always named properly, either due to a web browser mangling an extension or for whatever reason. When a file is more than meets the eye, we must rely on the various tools available to use to determine what in fact it is.
+====The file utility====
+In UNIX there is a nifty little utility called **file** that attempts to determine the actual type of a file by checking a series of properties. From the **file**(**1**) man page:
+There are three sets of tests, performed in this order:
+  - filesystem tests,
+  - magic number tests,
+  - and language tests.
+The first test that succeeds causes the file type to be printed.
+A //filesystem// test checks to see if the file is non-ordinary (such as a socket, symbolic link, or other special file).
+The //magic number// test is a check of files conforming to existing fixed formats, typically by examining the file at the binary level. If using a hex editor, you will find that **.gz** files should always start with the same sequence of hexadecimal values.
+Finally, if the file is determined to be a simple ASCII file, it will attempt to analyze whether or not it conforms to some language (ie C source code vs. an HTML document).
+Note that **file** is not always perfect, but for most cases will get the job done. Try checking files in your home directory or elsewhere on the system and see the results.
+Refer to the **file**(**1**) manual page or your textbook for more information.
+=====Practice=====
+For this project, files are located in the **projects/puzzlebox/** subdirectory of the UNIX Public Directory.
+^    ^|Do the following, and discuss the results in your Opus:|
+| ^  a.|Copy **file.txt** into your home directory.|
+|:::^  b.|Using **file**(**1**), what type of file does this appear to be?|
+|:::^  c.|View the contents of this file using **cat**(**1**). Is it what it appears to be?|
+|:::^  d.|Using **gzip**(**1**), compress this file with default compression. What does **file**(**1**) say?|
+|:::^  e.|Uncompress the file, and recompress using arguments for fastest (not highest) compression. What does **file**(**1**) report now?|
+As in many puzzles, one's visual comprehension of the scenario plays a vital role. Where something doesn't necessarily meet the eye, or is not behaving as you would expect- just try reading any messages or output. Sometimes the clues are right under your nose.
+=====Procedure=====
+Try your hand at the following activity, where things are not necessarily as they should be:
+  * Locate the file **puzzle.txt** and copy it into your home directory.
+Being a file that ends in **.txt**, you might try opening it in a text editor (or simply using the **cat**(**1**) utility.
+Does it appear to be a text file?
+  * Use the **file**(**1**) utility to determine the actual file type.
+  * Based on the output of file, react as appropriate to unravel this puzzle in order to find some plain text directions that will instruct you how to finish this project.
+As is the case many investigations, just observing how things behave can lead to recognition of an object's true state, or the recognition of a pattern, which can be used to solve the task at hand.
+=====Submission=====
+To successfully complete this project, you must follow the directions located in a readable file at the conclusion of this project. Until you encounter it, you are not yet finished (hint).
+You should get some sort of confirmation indicating successful submission (actually, two) if all went according to plan. If not, check for typos and or locational mismatches.

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