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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
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Commands by h3nr1x from sorted by
Terminal - Commands by h3nr1x - 5 results
read -s -p"Password: " USER_PASSWORD_VARIABLE; echo
2011-07-20 20:22:42
User: h3nr1x
Functions: read
Tags: read

You can ask repeatedly for a non-blank password using this function:

function read_password() {

while [ ! -n "$USER_PASSWORD" ]; do

read -s -p"Password: " USER_PASSWORD

if [ ! -n "$USER_PASSWORD" ]; then

echo "ERROR: You must specify a valid password, please try again"





Also you can set a time out (in seconds) to write the password

read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE

if [ ! $? -eq 0 ]; then

echo "Time out!"


compgen -c | sort -u > commands
2011-06-28 00:29:15
User: h3nr1x
Functions: sort
Tags: compgen

When you press TAB twice in your prompt, bash tells you something like

"Display all 4567 possibilities? (y or n)"

But when you press "y" you only get the list in the terminal output and, if you want to save it to a file, you have to copy it by hand from the vterm screen. With this utility you save the list to a file or pipe it to another command at will

You can use the file saved list to grep for a particular pattern, useful if you are searching for a command but you only remember a few letters

type {command} >/dev/null
2011-06-22 15:30:57
User: h3nr1x
Functions: type

Usefull to detect if a commad that your script relies upon is properly installed in your box, you can use it as a function

function is_program_installed() {

type "$1" >/dev/null


Invoke it and check the execution code

is_program_installed "dialog"

if [ ! $? -eq 0 ]; then

echo "dialog is not installed"

exit 1


FILE=$(tempfile 2>/dev/null || echo .$RANDOM)
2011-06-22 15:12:21
User: h3nr1x
Functions: echo

Another way to create temp files in your scripts, if tempfile fails, it will create a hidden local file in the current directory, don't forget to delete $FILE

cat /etc/issue
2011-06-22 15:04:45
User: h3nr1x
Functions: cat

Another way of do it in debian like distros, don't know if works for others