Linux Command Line Basics
There are a number of good resources on the web. Here's one of them:
Commands you should know
Changing Your Password
Note: this does not apply to users who log in with their Unity Id and password.
passwd
There is a 12-character minimum length requirement on the cluster.
Navigation
pwd - print working directory ls - list files cd - change directory less - file pager file - describes type of a file
File Manipulation
cp - copy mv - move (rename) rm - remove (delete) mkdir - make directory rmdir - remove directory
Editing Text
Choose an editor:
nano vi emacs
Basic Script
#!/bin/bash ...
Make a script file “executable”:
chmod u+x scriptname
Getting More Information
man COMMAND man ls
IO Redirection
Save output from a command to file.
ls > file.txt
Terminal Multiplexing
This lets you run multiple terminals that are immune to “hang-ups” (network errors) and can remain active even after you log out. You “detach” from the terminal and then re-attach after logging back in.
screen
Other terminal multiplexers (byobu, tmux) are also installed on the cluster.
Finding Files
Find a file by name:
find . -name lost_file.txt
find is a very flexible (and quite complicated) tool for finding files and applying commands to the results. It's well worth learning more about this command.
Disk Space Use
Calculate the total size of a directory:
du -sh dirname