- A Cloud Guru
Getting Help at the Command Line
Linux systems have an average of 3,000 commands on them, so it's not feasible to know more than a couple of hundred of the commands well. In this lab, we'll discover how to find out more information about commands and files on the system.
Table of Contents
Use Built-In Help and External Help Commands to Find Out More About a Given Command
Get help for a command
Output the help to a file so it can be searched
ls --help > lshelp.txt
Scroll through the file:
Quit out of it by hitting q.
Find out what will run with
See if there are more on the system:
which -a ls
Find out more information about a command:
Find out what a command is:
Use the `man` Command and Related Utilities to Find Out More Information on Desired Commands
man -f crontab
This will show us the sections.
There will be a table that shows us the section numbers. Quit out of it by hitting q.
man -f crontab man 5 crontab
This takes us to the configuration file format of crontab. Quit out of it by hitting q.
If we don't know which one we want, enter:
man -a crontab
It will show us the first one. Quit by hitting q. if we want the next one. Hit Enter.
Investigate Additional Sources of Documentation on the System `tree`
Run the following:
tree -H '/usr/share/doc/packages' -L 1 --noreport --charset utf-8 > ~/packages_index.html
treeis not installed, you can install it by running
sudo -i zypper in tree.
What's a lab?
Hands-on Labs are real environments created by industry experts to help you learn. These environments help you gain knowledge and experience, practice without compromising your system, test without risk, destroy without fear, and let you learn from your mistakes. Hands-on Labs: practice your skills before delivering in the real world.