Hide

What's this?

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.


Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

UpGuard checks and validates configurations for every major OS, network device, and cloud provider.
Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

Hide

News

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!
Hide

Top Tags

Hide

Functions

Commands tagged CLFUContest from sorted by
Terminal - Commands tagged CLFUContest - 21 results
NSPR_LOG_MODULES=nsHostResolver:5 NSPR_LOG_FILE=/tmp/log.txt /Applications/Firefox.app/Contents/MacOS/firefox
NSPR_LOG_MODULES=nsHostResolver:5 NSPR_LOG_FILE=/tmp/log.txt firefox
dnstop -l 3 enp1s0f0
xidel --quiet 'http://www.ebay.com/sch/Beds-Bed-Frames-/175758/i.html?_from=R40&_sac=1&_sop=15&_nkw=bed' -e 'css(".lvresult")[not(matches(., "Pickup only|BUILDING PLANS \(ONLY\)|PARTS LIST"))]/css(".lvtitle")/(.||": "||a/@href)' -f 'css("a.gspr.next")'
2015-09-24 12:11:13
User: BeniBela
0

The ebay URL is the search query copied from the browser (here searching for bed stuff). The regex is for crap that should not be shown. Important is "Pickup only", which filters away all the things that cannot be shipped (a filter that cannot be done on Ebay's webpage).

It will output the title and url for all matching items, for all pages of the search result.

It also works for the German Ebay.

curl -q -s http://www.hasthelhcdestroyedtheearth.com/ | sed -En '/span/s/.*>(.*)<.*/\1/p'
2015-09-23 23:26:30
User: Tatsh
Functions: sed
0

Use -q as first argument (as described in `man curl`) to ignore curlrc to ensure the output is always the same regardless of user's configuration.

while true; do (echo -n $(date +"%F %T"):\ ; xwininfo -id $(xprop -root|grep "ACTIVE_WINDOW("|cut -d\ -f 5) | grep "Window id" | cut -d\" -f 2 ) >> logfile; sleep 60; done
2015-09-23 23:00:14
User: BeniBela
Functions: cut date echo grep sleep
2

This logs the titles of the active windows, thus you can monitor what you have done during which times. (it is not hard to also log the executable name, but then it is gets too long)

xidel --quiet http://www.hasthelhcdestroyedtheearth.com/ -e //span
2015-09-23 12:31:55
User: BeniBela
1

This says if the LHC has destroyed the world. Run it in a loop to monitor the state of Earth. Might not work reliable, if the world has actually been destroyed.

curl -s http://www.hasthelhcdestroyedtheearth.com/ | sed -En '/span/s/.*>(.*)<.*/\1/p'
2015-09-23 12:30:31
User: BeniBela
Functions: sed
1

This says if the LHC has destroyed the world. Run it in a loop to monitor the state of Earth. Might not work reliable, if the world has actually been destroyed.

while true; do nc -z localhost 3333 >|/dev/null || (ssh -NfL 3333:REMOTE_HOST:5432 [email protected]_HOST); sleep 15; done
2015-09-21 02:25:49
User: rxw
Functions: sleep ssh
-1

Check if SSH tunnel is open and open it, if it isn't.

NB: In this example, 3333 would be your local port, 5432 the remote port (which is, afaik, usually used by PostgreSQL) and of course you should replace REMOTE_HOST with any valid IP or hostname. The example above let's you work on remote PostgreSQL databases from your local shell, like this:

psql -E -h localhost -p 3333
f=bigdata.xz; calc "round($(lsof -o0 -o "$f"|awk '{o=substr($7,3)}END{print o}')/$(stat -c %s "$f")*100)"
2015-09-19 18:27:12
User: unhammer
2

Say you're started "xzcat bigdata.xz | complicated-processing-program >summary" an hour ago, and you of course forgot to enable progress output (you could've just put "awk 'NR%1000==0{print NR>"/dev/stderr"}{print}'" in the pipeline but it's too late for that now). But you really want some idea of how far along your program is. Then you can run the above command to see how many % along xzcat is in reading the file.

Note that this is for the GNU/Linux version of lsof; the one found on e.g. Darwin has slightly different output so the awk part may need some tweaks.

while cat energy_now; do sleep 1; done |awk -v F=$(cat energy_full) -v C=60 'NR==1{P=B=$1;p=100/F} {d=$1-P; if(d!=0&&d*D<=0){D=d;n=1;A[0]=B=P}; if(n>0){r=g=($1-B)/n;if(n>C){r=($1-A[n%C])/C}}; A[n++%C]=P=$1; printf "%3d %+09.5f %+09.5f\n", p*$1, p*g, p*r}'
2015-09-19 15:45:40
User: sqweek
Functions: awk cat printf sleep
-1

Needs to be run in a battery sysfs dir, eg. /sys/class/power_supply/BAT0 on my system.

Displays the battery's current charge and the rate per-second at which energy is {dis,}charging. All values are displayed as percentages of "full" charge.

The first column is the current charge. The second is the rate of change averaged over the entire lifetime of the command (or since the AC cable was {un,}plugged), and the third column is the rate of change averaged over the last minute (controlled by the C=60 variable passed to awk).

The sample output captures a scenario where I ran 'yes' in another terminal to max out a CPU. My battery was at 76% charge and you can see the energy drain starts to rise above 0.01% per-second as the cpu starts working and the fan kicks in etc. While idle it was more like 0.005% per-second.

I tried to use this to estimate the remaining battery life/time until fully charged, but found it to be pretty useless... As my battery gets more charged it starts to charge slower, which meant the estimate was always wrong. Not sure if that's common for batteries or not.

[ $(date +"%H") -lt 7 ] && echo you should probably be sleeping...
weather() { curl -s "http://www.wunderground.com/q/zmw:$1.1.99999" | grep "og:title" | cut -d\" -f4 | sed 's/&deg;/ degrees F/'; }
while true; do date; ps auxf | awk '{if($8=="D") print $0;}'; sleep 1; done
curl -sL http://goo.gl/3sA3iW | head -16 | tail -14
followers() { curl -s https://twitter.com/$1 | grep -o '[0-9,]* Followers'; }
2015-09-19 07:07:36
Functions: grep
Tags: CLFUContest
0

See how many people are following you (or anyone) on Twitter.

followers cadejscroggins
last|grep `whoami`|grep -v logged|cut -c61-71|sed -e 's/[()]//g'|awk '{ sub("\\+", ":");split($1,a,":");if(a[3]){print a[1]*60*60+a[2]*60+a[3]} else {print a[1]*60+a[2] }; }'|paste -s -d+ -|bc|awk '{printf "%dh:%dm:%ds\n",$1/(60*60),$1%(60*60)/60,$1%60}'
2015-09-19 03:02:43
User: donjuanica
Functions: awk cut grep last paste sed
-1

Add -n to last command to restrict to last num logins, otherwise it will pull all available history.

dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
watch "awk '/Rss/{sum += \$2; } END{print sum, \"kB\"}' < /proc/$(pidof firefox)/smaps"
2015-09-19 00:36:34
User: gumnos
Functions: watch
2

Sometimes top/htop don't give the fine-grained detail on memory usage you might need. Sum up the exact memory types you want

echo "1 BTC = $(curl -s https://api.coindesk.com/v1/bpi/currentprice/usd.json | grep -o 'rate":"[^"]*' | cut -d\" -f3) USD"
wget https://medium.com/@commandlinefu/holy-fsck-a-contest-cd320952726b
2015-09-18 23:57:23
User: jonhendren
Functions: wget
Tags: CLFUContest
0

Here?s the idea: Submit a one-liner that returns a value or string usable for monitoring something. The more interesting/important, the better.

Tag your one-liners with CLFUContest to enter. Whether you?re participating or not, be sure to vote on the other submissions. The top 5 contest entries by vote count will receive a $10 Amazon gift certificate. On top of that, we?ll select our 3 favorite entries to receive $25 Amazon gift certificates. The prizes might even overlap! Feel free to enter as many times as you like. Check out the URL above for the fine print.

-Admin