======BASH======
===== Set VIM as visudo =====
Run as root
<code>echo "export EDITOR=vim;" >> ~/.bashrc</code>

From
<code>VISUAL="vim" ; export VISUAL
EDITOR="$VISUAL" ; export EDITOR</code>

===== Read File =====
Read a list of words from a file [[https://blog.apnic.net/2023/07/19/the-joy-of-txt/|source]]

<code>#!/bin/bash
domainsfile="domains.txt"

while read domain
do
    echo "--"
    echo "[$(date)] CHECKING DOMAIN $domain"
    echo "--"

    host -W 5 -t txt "$domain". # -W 5 for a 5 second timeout
done < "$domainsfile"</code>
<code>./get-txt-records.sh > host.out 2>&1</code>
===== Sudo =====
Add user to sudo list in ''visudo''
<code>username ALL=(ALL:ALL) ALL</code>
The add user where they don't need password, use the following.

REMEMBER: put this at the bottom of the file or other lines may get applied after this and change the user permission.
<code>username ALL=(ALL) NOPASSWD: ALL</code>
=====Toggle Bash History=====
Turn Off<code>set +o history</code>
Turn on<code>set -o history</code>
=====Convert to Uppercase=====
<code>echo ${VARNAME^^}</code>
=====Convert to Lowercase=====
<code>echo ${VARNAME,,}</code>

=====Copy and Preserve Permissions=====
Add -p to the cp command to preserve ownership and permissions 
=====Copy Permissions=====
To replicate the permissions of one file onto a second file, use the following
<code>chown --reference=file1 file2
chmod --reference=file1 file2
restorecon --reference=file1 file2</code>
=====cat Multiple Lines=====
This will append the text to outputfile.txt. Replace <code><<</code> with <code><</code> to overwrite the entire file.
<code>cat << EOF >> outputfile.txt
Line1 - The first line
Line2 - The middle line
Line3 - The last line
EOF</code>
=====Polish Start/Stop Scripts=====
On CentOS, you can use echo_success and echo_failure to add [ OK ] and [ FAILED] to the screen
<code>#!/bin/bash
# This next line must be included
. /etc/init.d/functions

echo -n "Starting My Service:"
# Success or Failure will depend on whether the function
# start_my_service_function returns a 0 or a non0 number
start_my_service_function && echo_success || echo_failure
echo</code>
===== Bash Colour =====
<code>LS_COLORS='rs=0:di=1;35:ln=01;36:mh=00:pi=40;33:so=01;35:do=01;35:bd=40;33;01:cd=40;33;01:or=40;31;01:su=37;41:sg=30;43:ca=30;41:tw=30;42:ow=34;42:st=37;44:ex=01;32:*.tar=01;31:*.tgz=01;31:*.arj=01;31:*.taz=01;31:*.lzh=01;31:*.lzma=01;31:*.tlz=01;31:*.txz=01;31:*.zip=01;31:*.z=01;31:*.Z=01;31:*.dz=01;31:*.gz=01;31:*.lz=01;31:*.xz=01;31:*.bz2=01;31:*.bz=01;31:*.tbz=01;31:*.tbz2=01;31:*.tz=01;31:*.deb=01;31:*.rpm=01;31:*.jar=01;31:*.war=01;31:*.ear=01;31:*.sar=01;31:*.rar=01;31:*.ace=01;31:*.zoo=01;31:*.cpio=01;31:*.7z=01;31:*.rz=01;31:*.jpg=01;35:*.jpeg=01;35:*.gif=01;35:*.bmp=01;35:*.pbm=01;35:*.pgm=01;35:*.ppm=01;35:*.tga=01;35:*.xbm=01;35:*.xpm=01;35:*.tif=01;35:*.tiff=01;35:*.png=01;35:*.svg=01;35:*.svgz=01;35:*.mng=01;35:*.pcx=01;35:*.mov=01;35:*.mpg=01;35:*.mpeg=01;35:*.m2v=01;35:*.mkv=01;35:*.webm=01;35:*.ogm=01;35:*.mp4=01;35:*.m4v=01;35:*.mp4v=01;35:*.vob=01;35:*.qt=01;35:*.nuv=01;35:*.wmv=01;35:*.asf=01;35:*.rm=01;35:*.rmvb=01;35:*.flc=01;35:*.avi=01;35:*.fli=01;35:*.flv=01;35:*.gl=01;35:*.dl=01;35:*.xcf=01;35:*.xwd=01;35:*.yuv=01;35:*.cgm=01;35:*.emf=01;35:*.axv=01;35:*.anx=01;35:*.ogv=01;35:*.ogx=01;35:*.aac=00;36:*.au=00;36:*.flac=00;36:*.mid=00;36:*.midi=00;36:*.mka=00;36:*.mp3=00;36:*.mpc=00;36:*.ogg=00;36:*.ra=00;36:*.wav=00;36:*.axa=00;36:*.oga=00;36:*.spx=00;36:*.xspf=00;36:';
export LS_COLORS

PS1='\e[37;1m\u@\e[35m\W\e[0m\$ ' # this will change your prompt format</code>

<code>echo "set background=dark" >> .vimrc</code>

===== Other =====
<code>alias ipconfig='ip address show wlp3s0 | grep inet'
alias dns='resolvectl status wlp3s0'
alias dnswifi='resolvectl status wlp3s0'
alias dnslan='resolvectl status enp0s25'
alias dig="grc dig"
alias nmap="grc nmap"</code>