LPI Linux Certification in a Nutshell, 2nd Edition

Documentation (Topic 1.108)

Review Questions

1. Describe the PAGER environment variable.

   1. How does it affect the man facility?

   2. If PAGER is not set, how does man display output?

   3. Does this environment variable affect the info facility?

2. In response to your query on a library function, man returns a page on an identically named user command. Why does this happen?

   1. How do you display the page for the function and not the command?

   2. How do you display both?

3. Name the program that displays GNU texinfo pages.

Exercises

Exercise 1.108-1. man and /usr/doc

1. Run a man inquiry as follows:

   $ man -a -Pless mkfifo

   There are both an mkfifo command and an mkfifo function. You'll be looking at the mkfifo command from section 1 of the manual. Note MKFIFO(1) at the top of the page.

   Press q to terminate the pager program. The pager is then invoked again and displays the mkfifo function from section 3 of the manual. Note MKFIFO(3) at the top of the page.

   Run the man command again, using the -Pmore option as follows:

   $ man -a -Pmore mkfifo

   1. What differences do you see in the output?

   2. What does the -P option do?

2. Run another man inquiry as follows:

   $ man -d ln

   1. What output do you get from man?

   2. What is the -d option?

   3. Did you see information on the ln command?

3. Now examine the man configuration file:

   $ less /etc/man.config

4. Notice how the contents of this file coincide with the result you received from the -d option.

Exercise 1.108-4. Acting as a Linux helpdesk

Suppose you are a help desk technician in a mixed-systems office, and you are relatively ...