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

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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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!

Top Tags



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 tagged epoch from sorted by
Terminal - Commands tagged epoch - 9 results
sajb {$ip="";$old=0;while(1){$up=test-connection -quiet -count 1 $ip;if($up-ne$old){$s=(date -u %s).split('.')[0]+' '+(date -f s).replace('T',' ')+' '+$ip+' '+$(if($up){'Up'}else{'Down'});echo $s|out-file -a $home\ping.txt;$old=$up}sleep 10}}

IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type


Uses sajb to start a PowerShell background job that pings an IP host every 10 seconds.

Any changes in the host's Up/Down state is time-stamped and logged to a file.

Date/time stamps are logged in two formats: Unix and human-readable.

A while(1) loop repeats the test every 10 seconds by using the sleep command.

See the Sample Output for more detail.

I use this command to log Up/Down events of my Motorola SB6141 cable modem (

To end the logging, close the PowerShell window or use the "exit" command.

date -r 1390196676
perl -MPOSIX -le 'print strftime "%F", localtime 1234567890'
date +%s
2012-03-12 00:14:22
User: akhilravidas
Functions: date
Tags: date epoch

Get the time since epoch. Useful when working with commands and logs which use this format.

date -d '2011-12-15 05:47:09' +"epoch: %s or format: %Y/%m/%d"
perl -le 'print scalar gmtime shift' 1234567890
truss date 2>&1 | awk '/^time/{print $3}'
perl -e 'print scalar(gmtime(1234567890)), "\n"'
echo "0t${currentEpoch}=Y" | /usr/bin/adb
2009-08-25 12:17:01
User: verboEse
Functions: echo

this works on Solaris, so not better than the "only-GNU"-tool :-(

I think, there is no one-liner for this, that will work on all *nix-es