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Final Exam Review

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Final exam: Tuesday December 13, 8:10-10:00 in Sloan 9.

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Notes:

1. The exam is about 30% longer than the midterm, but you have 110 minutes rather than 50 minutes

2. The exam is NOT comprehensive, except for two things:

· Debug macros

· Shell file name expansion

Final Exam Topics

• Debug macros: TRACE and DEBUG

• Very basics: what they do, advantage over mental analysis & interactive debuggers; also what assert is.
• Questions from midterm:

• (6 points) Describe how the assert macro works and how you use it in a program, and who its output is intended for.
• (5 points) What advantage does the TRACE macro discussed and demonstrated in class have over debugging with just fprintf or printf directly in your code?
• (7 points) Explain when and how the TRACE macro output is “turned on” (enabled” or “turned off” (disabled). If there is more than one way to do it, which is “best”, and why?
• (3 points) What advantage does the DEBUG macro package discussed and demonstrated in class have over debugging with the TRACE macro?

• Filters

• regular expressions

• Given a regular expression, understand what it will (and won't) match.
• Given an English phrase, come up with a regular expression that matches it
• Be able to do the above two things also with shell file name expansion

• tr
• diff
• sed

• Given a sed command, understand what the output will be.
• In s/OLD/NEW/g, how to use part (or all) of what is matched in OLD with NEW (e.g., \1)

• Don’t forget the advanced options and pattern primitives at the end of the notes.

• Awk

• Given an awk script, tell what it does.
• Write a simple awk script for a given problem.
• How to use something other than a newline for a record delimeter (see man page… there are two ways to do it, just know one)

• Shell programming

• Given a shell script, tell what it does.
• Write a simple shell script for a given problem

• Perl

• Given a perl script, tell what it does.
• Know some of the main language features, especially lists, arrays, and associative arrays.
• Know the basics of Functions, Misc. Control Structures, and Files.
• If you can do some things more than on way in Perl, be able to give more than one example! (E.g., ways to load in a key, value pair into an associative array.)

• Language differences (sed, awk, shell, perl)

• Understand the differences in the languages; an outstanding review can be found at the Perl traps page, and anything here is fair game.
• Know how "if-then-else if-else" is constructed in each language.
• Know what $0 means in each language.
• Know what $1, $2, $3, etc. means in each language.
• Know how to get command line arguments (except for sed).
• Know why you might want to use one language instead of the other.
• Typing differences: what happens for example if you go (except for sed)

• set a to 2
• set b to “foo”
• set c to a plus b

• I am not interested in teaching the very fine details (minutia) or rare boundary cases of syntax/semantics of a language, so focusing on that will help you at most a point or two, probably zero. I just want you to be as reasonably versed as the number of lectures and homework assignments can reasonably make a sophomore be.

• Future alumni training: Volunteer(s) for it