Useful Terminal Commands

From Liki

A list of useful *nix terminal commands and their functions:

Contents 1 Getting help 2 Directory Commands 3 Viewing and Editing Files 4 Searching Commands 5 Currently Uncategorized

[edit] Getting help

In almost all cases, typing

$ <command> --help

or

$ man <command>

will give help on the specifics for a particular command. If those fail, look on the liki, [Google] it, or ask somebody.

[edit] Directory Commands

commands for editing the directory structure:

command	action
ls	list directory contents
mkdir	make a directory
rmdir	remove an empty directory
rm	remove a file
mv	move a file
cp	copy a file

Warning rm, mv, and cp are potentially destructive (whoops, there goes my research directory... etc.). To avoid doing something you'll regret later, it's wise to place something like

alias rm='rm -iv'
alias cp='cp -iv'
alias mv='mv -iv'

in your ~/.bashrc file (try nano ~/.bashrc). This makes the commands interactive by default and prints messages showing what files are being moved, deleted, etc.

[edit] Viewing and Editing Files

command	action
cat	print a file to the terminal
less	allow scrolling through large program output (paginate)
nano	simple text editor. Helpful shortcuts are listed at the bottom of the screen.
emacs	complicated text editor. The shortcuts are in your head, but you can write your own.
vi	another complicated text editor. Whatever works for you.

[edit] Searching Commands

command	action
find	search for a file (slow, but lots of features).
locate	search for a file in a pre-compiled index (fast).
grep	search a file (or stdin) for matching regular expressions.

[edit] Currently Uncategorized

command	action
pwd	print working directory.
ssh	Secure SHell. Log in to remote computers.
scp	Secure CoPy. Copy files to/from remote computers.
paste	merge files by row paste,join, sort article
join	intelligently merge files by row paste,join,sort article
sort	sort files by row paste,join,sort article
uniq	remove duplicate lines
cut	select particular columns from a file
awk	record editor for flat-text databases, general text processing.
sed	stream editor, search-replace, etc.
find	search for files
lsof	list open files
ps	show current processes