Introduction to Unix
Homework 8


1. Write a  Bash shell script program that takes the name of a file or
directory as an argument and reports if the file is a directory, regular file
or other and also reports if the user has read, write and execute permission on
the file or directory.  Use a sequence of if statements on the file name to
determine the information.


2. Write a Bash shell script program that takes two integer arguments.  The
second argument is assumed to be greater than the first.  The output of the
program is a counting of numbers beginning at the first number and ending with
the second number.  (Note, this simple script is surprising useful for a number
of activities when working with a Unix system.)

3. Write a Bash shell script program that will read a list of numbers from
standard input and the output is the sum of the numbers. 

4. Write a Bash shell script program that removes all zero length ordinary
files in the directory passed as an optional argument. If you do not specify
the directory argument, the script uses the present working directory as the
default argument. Do appropriate exception handling in your script.  Show a few
sample runs of your script.

5. (Extra Credit)  This one is a little bit trickier than it first appears.
Write a Bash shell script that will rename all the files in a directory.  It
will mostly be useful to rename digital picture files.  The first argument is a
base name, second argument is a file extension.  If it is run as: 

$ renumber 1stBirtday jpg

then the resulting files should have names like: 
1stBirthday001.jpg, 1stBirthday002.jpg,  1stBirthday003.jpg, etc.