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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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Commands by unixmonkey365 from sorted by
Terminal - Commands by unixmonkey365 - 6 results
for x in 8svx aif aifc aiff aiffc ... wv wve xa xi ; do echo $x ; play -q -t $x soundfile trim 0 3 ; done
2011-12-09 00:23:45
Functions: echo

I wasted two hours reading the sox documentation and searching on the web for the format of some obscure fscking sound sample, and then finally came up with this. This plays only the first three seconds of your unknown formatted sound file using every one of sox's built-in filetypes. If you don't get an exact match, you may get close.


I could not fit every single type in and keep it under 127 characters, so you will have to replace "..." with the full list obtainable by `$ sox --help` (or try `Show sample output`)


note: /usr/bin/play should be linked to sox on most systems.

# Negative is Not Nice
2011-11-29 19:05:23

This is just a phrase I use to help me remember which way is what when using nice (top, renice, etc.), and not a command, (unless you really want this in your .bash_history to help remind you.) I was using the command `man nice ` way too much just to look up which way is what. This saves 9 keystrokes every time I remember it.

Make sure you downvote me if you think mnemonics sux. Otherwise I hope this helps someone else.

strings ~/.mozilla/firefox/*/webappsstore.sqlite|grep -Eo "^.+\.:" |rev
2011-09-26 15:23:09
Functions: grep strings

Someone over at Mozilla dot Org probably said, "I know, let's create a super-duper universal replacement for browser cookies that are persistent and even more creepy and then NOT give our browser users the tools they need to monitor, read, block or selectively remove them!"


This will let you see all the DOM object users in all your firefox profiles. Feel free to toss a `| sort -u` on the end to remove dupes.


I highly recommend you treat these as "session cookies" by scripting something that deletes this sqlite database during each firefox start-up.


note: does not do anything for so-called "flash cookies"

crontest () { date '-d +2 minutes' +'%M %k %d %m *'; }
2011-09-16 00:47:24
Functions: date

Another function to stick into your .bashrc

This spits out the time two minutes in the future, but already formatted for pasting into your crontab file for testing without any thought required on your part. Frequently things don't work the way you expect inside a crontab job, and you probably want to find out now that your $PATH is completely different inside of cron or other global variables aren't defined. So this will generate a date you can use for testing now, and then later you can change it to run at 5:37 am on a Sunday evening.

alias cn='cat > /dev/null'
2011-09-16 00:00:28
Functions: alias

cn stands for "Cat Null"


The idea is that sometimes you run across something on maybe a webpage - like commandlinefu - that you want to try out on your terminal. You could put a '#' in and then paste it, but what if it is several lines?


This command will echo the pasted characters to the screen and divert them to the bit bucket.


Put this simple alias in your .bashrc, hit cn, paste away, and hit a ctrl+c or a ctrl+d when you are done to get your prompt back.

timeDNS () { { for x in "${local_DNS}" "" "" "" "" "" "" "" ""; do ({ echo -n "$x "; dig @"$x" "$*"|grep Query ; }|sponge &) done ; } | sort -n -k5 ; }
2011-08-18 01:11:53
Functions: dig echo grep sort

Evoke from the command like as:

timeDNS commandlinefu.com


This isn't too terribly practical, but it is a good code example of using subshells to run the queries in parallel and the use of an "anonymous function" (a/k/a "inline group") to group i/o.


I'm assuming you have already defined your local DNS cache as ${local_DNS}, (here, it's


You do need to install `moreutils` to get `sponge`.


If you're willing to wait, a slower version w/o sponge, (and w/o sorting), is this:


DNS () { for x in "" "" "" "" "" "" "" "" ""; do (echo -n "$x "; dig @"$x" "$*"|grep Query) ; done ; }