CS114: Homework 1

Do all of the problems below. Turn in your answers (hardcopy) to problems 2 and 3 with your full name and netID, in class or in my mailbox (657 Rhodes) by 5 p.m. on the due date given on the main course page.

Problem 1

Ensure that you have a CSUG account. Login to one of the linux machines in CSUG. (e.g. csug01.csuglab.cornell.edu). If you cannot login, contact the instructor immediately.

Problem 2

What is the full path to your home directory? What files and directories are in your home directory? What files are in the /var directory?
Use this opportunity to explore. Look at the man pages for the commands discussed so far. You are welcome to look in other system directories such as those in /bin, /lib, /usr, etc.; it is inappropriate to read the files or directories of other users without their permission, even if their Unix permissions are set to allow it.

Problem 3

• Read the man page for the command ls. What options would you use to list the files so that the most recently modified file appears last?
• Read the man page for the command find in enough detail to answer the following questions. Since there is also a C++ library function named find, you may need to run man -s 1 find to get the correct man page. This specifies that the term find should be sought in Section 1 of the manual (commands), not in Section 3 (library functions). Be sure to look at the examples.
  • What arguments would you give to print all files under your home directory (and subdirectories) named "index.html"?
  • What does the -mtime option do?
  • What is done differently when the argument -mtime 7 is given versus -mtime -7?
• What UNIX program could you use to do arithmetic calculations using reverse Polish notation? Where is it installed?