IT244: Introduction to Linux/UNIX – Fall 2010
Homework 5
Due: Monday, 11/17/2010
Chapters 8, 12, 13:
NOTE: For all scripts that you are asked to write, please make sure that
you write an actual script on Linux (sf05.cs.umb.edu) and test it.
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1) (10 points) Q. 5.
 For part b, the question is asking why, for the needs of the
script, cat would be used for the second input.
NOTE: cat with no arguments takes input from the
command line. To end the input, enter Ctrl-D. Type
this script in and run it for yourself.
2) (10 points) Q. 6.
 Make sure that you explain not only what happens in each
of the two cases, but why it happens.
3) (10 points)
 Write a login script (.bash_profile) that does the following:
i. Set a feature on your bash shell session so that during
your shell session you can set a variable and it will be
automatically exported for child processes to access.
ii. Adds your personal bin directory (~/bin) at the end
of the PATH variable.
iii. Change the invocation of the ls command so that in a
login session it always displays a long listing (ls –l)
even when you only type ls with no options.
iv. Set a feature on your bash shell session so that
command line editing can be done in vi editing mode.
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4) (10 points) Q. 1.
5) (10 points) Q. 2.
6) (10 points) Q. 4.
 On sf05.cs.umb.edu, use the /etc/login.defs file instead of
the file that the book gives, and search for the string ENAB.
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7) (10 points) Q. 3.
8) (10 points) Q. 4.
9) (10 points) Q. 5.
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