MinorAssignment4

The repo for CSCE 3600 Minor Assignment 4

##TODO ...

##Minor Assignment #4 – Converting SuperBash Programs to Bash

##Note: This assignment is being updated on 2/13/15 (Friday the 13th) and will soon (I hope) replace the current version on Blackboard. I will put changes/additions in red. Reasons for the changes will be discussed in class today. Also, the due date for this assignment will be changed from 2/16 to 2/23.

In this assignment you will write a C program that takes an advanced bash (bash++ ?) program and outputs a standard bash program that has no syntax errors. You are to complete this assignment in as a group, using your already assigned groups. You will also submit the assignment as a group. Make sure to include the names of all group members who worked on the assignment in comments within your C program. As in the past, only the group submission will be graded. We will NOT grade both a group submission and any singleton submissions from the same group.

So, there are two features of bash++ (no its NOT an OO language) that are not supported by bash in general, namely: 1) bash does not allow spaces, tabs or newlines around the "=" symbol used in initialization, and 2) the "then" keyword in bash if statements must be on a different line than the if itself. Also, the brackets ([,]) in bash’s conditionals must have spaces between the bracket and the condition itself. So, the following two statements (legal in bash++) are not acceptable to bash,

num    =                0            
if [x -lt 5] then ...

Your preprocessor will need to change those two statements (and others like them) in the output to be:

num=0
if [ x -lt 5 ]
then

or, if you prefer the if statement could become:

if [ x –lt 5 ] ; then

because, as in C the ; denotes a new “statement” (ok, line in Bash).

Again as a "preprocessor" your program will not actually change the input file itself but rather copy the input file to output making the necessary changes to the output file to make it "bashable".

THREE items which may seem to you to be choices of the implementation are in fact REQUIRED, namely

1. The program MUST be written in C, not C++ (or java, bash, ruby, …). If it is not written in C even if it “works” for minor 4 I guarantee it will NOT work in the context I will require for a future assignment.

2. The name of the bash++ file must be passed to your C program’s executable as command line argument 1. And any command line arguments required for the bash++ program will (must be) passed to your C program’s executable as command line arguments 2 .. n

3. Your program should use file I/O (I/O requiring specific open and close commands) sparingly. In fact, the ONLY file that should be opened is the bash++ file whose name is passed as argument 1.

In order to make the assignment a bit easier, I will provide some “conventions” for the bash++ files that will be used as test input. Those conventions are:

1. Any assignment statement (of the form identifier = some expression) will start in column 1. By that I mean there will be no spaces or tabs before the start of the identifier.

2. Any Unix commands (ls, wc, …) will NOT start in column 1, so there will be spaces before the name of the command. There is one exception. Echo may have spaces in front of it, but won’t necessarily have them.

3. Any bash reserved (or key) words can start anywhere on a line. Use your creativity (i.e. favorite search engine) to find the list of bash reserved words.

You will submit your single C file (that is your working program) to Blackboard at or before (newly) the stated deadline.

Good luck. (You'll likely need it.)

UPDATE TO ASSIGNEMENT HAS BEEN MADE AND HAS BEEN EXTENDED TO 2/23/15*******