RANDOMXAL

Just Random Stuff

Regex for IP (Starting with zero is included)

^((?![3-9][0-9]{2}|2[6-9][0-9]|25[6-9])[0-9]{1,3}\.){3}(?![3-9][0-9]{2}|2[6-9][0-9]|25[6-9])[0-9]{1,3}$

Password generator in a SHELL

echo -e {1..20}"\r$(tr -dc a-z0-9A-Z < /dev/random | head -c 20)\n"

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'sed' command examples

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Print additional 3 lines after pattern matchs

cat somefile.txt | sed  -n '/pattern/ {N;N;N;p}'

Print N-th colored output after patter match

cat somefile.txt | sed -e  '/pattern/ { s/^/\x1b[32m/; N;N;N; s/$/\x1b[0m/}'

Match text from pattern1 to patter2

cat somefile.txt | sed  -n '/pattern1/,/pattern2/p'

Cut out text in between pattern1 and patter2

cat somefile.txt | sed  -e 's/.*pattern1\(.*\)pattern2.*/\1/'

Color the text from pattern1 to pattern2

cat somefile.txt | sed -e '/pattern1/,/pattern2/ { s/^/\x1b[32m/; s/$/\x1b[0m/}'

To match brackets use HEX \x27="'"

For loop replacement in line here "t" is the operator for loop

echo ",,;;,,,,;;;," | sed ':loop; s/,,/,/; t loop'

To pass the variable in 'sed', double quotes are required around SED script OR put the variable inside the single quotes

1. cat somefile.txt | sed -e "s/pattern/$ANY_VARIABLE/g"
2. cat somefile.txt | sed -e 's/pattern/'$ANY_VARIABLE'/g'

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'bash' examples

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• 'name' will be the variable. name="my.own.domain.org" (in this case "." is only delimiter "." can be any character)

• echo ${name%.*}

  • result : my.own.domain

• echo ${name%%.*}

  • result : my

• echo ${name#*.}

  • result : own.domain.org

• echo ${name##*.}

  • result : org

• echo ${#name}

  • result : number length of the string

• echo ${name^^}

  • result : All Upper case

• echo ${name,,}

  • result : All Lower case

• echo ${name::3}

  • result : Displays first 3 characters

• echo ${name:3}

  • result : Displays all except first 3 characters

• echo ${name:3:5}

  • result : Skips 3 first characters and displays following 5

• echo ${name/st1/st2}

  • result : Replace first match 'st1' with 'st2' in 'name'

• echo ${name//st1/st2}

  • result : Replace all match 'st1' with 'st2' in 'name'

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Get GNOME's current theme name

gsettings get org.gnome.desktop.interface gtk-theme