COP 3344-01 Introduction to Unix: Lecture 10

Learning objectives

After this class, you should be able to:

1. Write Perl scripts using the following features: (i) arrays, (ii) command line arguments, (iii) file I/O, (iv) split, (v) system, and (vi) while.

Reading assignment

1. JEA: section 35.12-35.16, 15.19.
2. Lecture slides: Lecture 10.

Exercises and review questions

• Questions on current lecture's material
  1. Write a Perl script called mycp1 that takes two command line arguments. A call to ./mycp1 file1 file2 should copy file1 to file2. Do not use the system call.
  2. Write a Perl script called mycp2 that takes two command line arguments. A call to ./mycp2 file1 file2 should copy file1 to file2 using system and the cp command.
  3. Write a Perl script called field that takes three command line arguments. A call to ./field file linenum wordnum should output the wordnum th word on the linenum th line in the file file. For example, ./field file1 5 6 should print the 6 th word in the 5 th line of the file file1. (The words and lines should be numbered starting at 1, and not at 0.) Do not use the system call.

• Questions on next lecture's material
  1. Use printenv to list all your environment variables.