Fall 2007 CSci 553 Lab 1
Exercise 1.1
The instructor wants you to use a hitherto unknown command for
manipulating files. How would you get help on this command?
Exercise 1.2
Suppose ls shows you this:
Makefile biography.txt data enrolment.txt programs thesis
What argument(s) will make it print the names in reverse, like this:
thesis programs enrolment.txt data biography.txt Makefile
Exercise 1.3
What does the command cd ~ do? What about cd ~hpotter?
Exercise 1.4
What command will show you the first 10 lines of a file? The first 25?
The last 12?
Exercise 1.5
diff finds and displays the differences between two text files. For example,
if you modify earth.txt to create a new file earth2.txt that contains:
Name: Earth
Period: 365.26 days
Inclination: 0.00 degrees
Eccentricity: 0.02
Satellites: 1
you can then compare the two files like this:
$ diff earth.txt earth2.txt
3c3
< Inclination: 0.00
---
> Inclination: 0.00 degrees 4a5
> Satellites: 1
(The rather cryptic header "3c3" means that line 3 of the first file must be
changed to get line 3 of the second; "4a5" means that a line is being added
after line 4 of the original file.)
What flag(s) should you give diff to tell it to ignore changes that just insert
or delete blank lines? What if you want to ignore changes in case (i.e.,
treat lowercase and uppercase letters as the same)?
