Vikid’s Bash Cookbook

Some Simple Stuff

bash --version

ls -adFlLQrRS1

pwd -L, pwd -P

type which, type -a which

apropos zip => man -k, locate which

find

stat, file -b

chsh -s /bin/bash

passwd -el

sudo cat /etc/shells

Common Shell Variables

$USER
$-             list all current option flags

Download a website

wget -r -np -k http://somesite.com

Options:

-r (recursive)
-np (don’t follow links to parent directories)
-k to make links in downloaded HTML or CSS point to local files
-nd (no directories): download all files to the current directory
-e robots.off: ignore robots.txt files, don’t download robots.txt files
-A png,jpg: accept only files with the extensions png or jpg
-m (mirror): -r –timestamping –level inf –no-remove-listing
-nc, –no-clobber: Skip download if files exist

Quoting

echo value is $3?!
echo "value is $3?!"
echo 'value is $3?!'

!" is history substitution

Sources and Links

Builtin Commands

ls () {
    builtin ls "@"
    echo "using defined ls"
}

Interactive

#!/usr/bin/env bash

case "$-" in
   *i*)
      echo "interative"
   *)
      echo "not interactive"
esac