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commandlinefu.com is the place to record those command-line gems that you return to again and again.

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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.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands by clockworkavian from sorted by
Terminal - Commands by clockworkavian - 4 results
true && { echo success;} || { echo failed; }
2009-04-02 01:49:25
Functions: echo true

This will perform one of two blocks of code, depending on the condition of the first. Essentially is a bash terniary operator.

To tell if a machine is up:

ping -c1 machine { echo succes;} || { echo failed; }

Because of the bash { } block operators, you can have multiple commands

ping -c1 machine && { echo success;log-timestamp.sh }|| { echo failed; email-admin.sh; }


Remember, the { } operators are treated by bash as a reserved word: as such, they need a space on either side.

If you have a command that can fail at the end of the true block, consider ending said block with 'false' to prevent accidental execution

whiptail --checklist "Simple checkbox menu" 11 35 5 tag item status repeat tags 1
2009-03-30 12:21:48
Tags: ncurses,

Not so much handy by itself, but very nice in shell scripts.

This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like:

"one" "two" "three" "four" "etc"

For those who prefer bash expansion over gratuitious typing:

whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} )

Things to note:

The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time.

If the status is 1, it will be selected by default. anything else, will be deselected.

function fork () { tf=$(tempfile -d /tmp -p $1.);echo -n "$tf "; $@ &>$tf& }
2009-03-25 23:33:54

This function runs a program in the background, and logs all output to an automatically created logfile. That way, you can still get at the output without it clogging up your terminal.


Throw fork() and this:

for prog in firefox kate konqueror ;do alias $prog="fork $prog";done

into your bashrc, so that they'll automatically run out of the way.

nmap 192.168.0-1.0-255 -sP
2009-03-23 22:19:05

Depending on the network setup, you may not get the hostname.