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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 using tee from sorted by
Terminal - Commands using tee - 98 results
echo "GRUB_INIT_TUNE=\"1000 334 1 334 1 0 1 334 1 0 1 261 1 334 1 0 1 392 2 0 4 196 2\"" | sudo tee -a /etc/default/grub > /dev/null && sudo update-grub
tail -f somefile |tee >(grep --line-buffered '1' > one.txt) |tee >(grep --line-buffered '2' > two.txt)
2011-04-03 10:05:28
User: binaryten
Functions: grep tail tee

when using named pipes only one reader is given the output by default. Also, most commands piped to by grep use a buffer which save output until tail -f finishes, which is not convenient. Here, using a combination of tee, sub-processes and the --line-buffered switch in grep we can workaround the problem.

tar -cvf - $DIR_TO_BACKUP | tee >(md5sum > backup_md5.txt) > /dev/st0 && mt -f /dev/nst0 bsfm 1 && md5sum -c backup_md5.txt < /dev/st0
2011-01-27 20:57:36
User: bugmenot
Functions: md5sum mt tar tee

Backups $DIR_TO_BACKUP into tape, creating on the fly a MD5SUM file of the backup.

Then rewinds one record on tape and checks if it's well written.

ls -la | tee ~/log.txt
echo wikileaks.com | sudo tee -a /etc/hosts
2010-12-13 03:31:07
User: matthewbauer
Functions: echo sudo tee

This one is a little bit easier for those of us that aren't always root.

CMD="who";SEC=1;N=0;OLD="";NEW=""; while `sleep $SEC`; do OLD="$NEW"; NEW="$(eval $CMD)"; DIFF=`diff <( echo "$OLD" ) <( echo "$NEW" )`; if [ -n "$DIFF" ]; then date; echo "Diff #$N (${SEC}s): $CMD"; echo "$DIFF"; fi; N=$[$N+1]; done | tee /tmp/keepr
2010-11-15 19:55:39
Functions: echo tee

Watch any command (pipes ok, quotes be careful) and keep history in a file. Good for watching and recording any kind of status or error condition, file creations, etc. The choice of "who" as CMD was just to show an obvious usage.

Uses plenty of shell tricks that can be disassembled for simpler stuff. It's deliberately not perfect, but it is generic, and can be customized for your own uses. Had to shorten a little to meet 255 chars.

Better than "watch" how? It keeps a date log of what is going on, and tee'd output is plain-text.

wget `youtube-dl -g 'http://www.youtube.com/watch?v=-S3O9qi2E2U'` -O - | tee -a parachute-ending.flv | mplayer -cache 8192 -
2010-10-28 13:51:59
User: artagnon
Functions: tee wget

Watch a video while it's downloading. It's additionally saved to the disk for later viewing.

ls |tee >(grep xxx |wc >xxx.count) >(grep yyy |wc >yyy.count) |grep zzz |wc >zzz.count
bash -i 2>&1 | tee /dev/stderr | nc -l 5000
2010-10-20 18:32:12
User: pykler
Functions: bash tee
Tags: nc

Doesn't work so well if you connect from windows. Linux only sends LF where windows wants CRLF. The alternative command works better with windows, however it uses script and a named pipe.

script -qf | tee >(nc -kl 5000) >(nc -kl 5001) >(nc -kl 5002)
2010-10-11 07:55:30
User: clvv
Functions: script tee
Tags: tee pipe script nc

run 'nc yourip 5000', 'nc yourip 5001' or 'nc yourip 5002' elsewhere will produce an exact same mirror of your shell. This is handy when you want to show someone else some amazing stuff in your shell without giving them control over it.

echo ondemand | sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
2010-09-21 10:24:42
User: bzaman
Functions: echo sudo tee

We sometimes need to change kernel parameters by echoing the file . This needs root privilege and if we do it using sudo like this , it fails

sudo echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

-bash: /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor: Permission denied

We can achieve this with the tee command by just doing sudo without logging as root user


echo "uptime" | tee >(ssh host1) >(ssh host2) >(ssh host3)
echo "tee can split a pipe in two"|tee >(rev) >(tr ' ' '_')
2010-08-14 20:38:59
User: axelabs
Functions: echo tee tr

Tee can be used to split a pipe into multiple streams for one or more process to work it. You can add more " >()" for even more fun.

wget -qO - http://www.google.com | tee >(md5sum) > /tmp/index.html
2010-07-23 06:29:29
User: jianingy
Functions: tee wget

other options:

* replace md5sum with sha1sum for SHA1 checksum

* replace '>' with '| tar zx' for extracting tarball

tee >(cat - >&2)
2010-07-20 17:22:31
User: camocrazed
Functions: cat tee

the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor.

In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount

dvgrab --format raw - | tee dvstream.dv | ffmpeg2theora -A 45 -V 400 -c 1 -f dv -x 360 -y 288 -o /dev/stdout - | tee savelivestream.ogv | oggfwd -p -d "Stream description" -n "Streamname" my.icecastserver.com 80 icecastpassword /stream.ogv
2010-05-25 11:23:46
User: dittaeva
Functions: tee

Streaming HTML5 compatible video (Ogg Theora video with Vorbis sound) to an Icecast server using dvgrab, ffmpeg2theora and oggfwd.

In this example I'm merging stereo sound to mono (-c 1), saving the original dv for later higher quality on-demand video (tee dvstream.dv), saving the theora stream for immediate on-demand video, and publishing the stream in Xiph's stream directory (-p and the name and description).

The URL of the video will be (depending on your server) http://my.icecastserver.com/stream.ogv which will play in newer Firefox, Chrome and Opera web browsers. Cortado (a Java player) can easily be used for IE.

Note also that I'm using port 80, which is not the default port for Icecast, this is to avoid restrictive firewalls.

Also note that ffmpeg2theora 0.25 and will heed the bitrates much better than former versions because of using libtheora 1.1 or newer.

rec -c 2 -r 44100 -s -t wav - | oggenc - | tee streamdump.ogg | oggfwd giss.tv 8000 password /mountpoint.ogg
2010-05-07 12:57:37
User: odaibanet
Functions: tee

easy way to setup an "internet radio sation", pre-requisite, create an account at an icecast server, in this example, just created beforehand an account at giss.tv.

Change the word password, with the respective real password you created at server.

Make sure to have installed rec, oggnec, oggfwd and tee.

I have a mixer connected at line in, so I can mix music and microphone.

This also will produce a local recorded copy of the session, it will be called "streamdump.ogg"

:w !sudo tee > /dev/null %
2010-03-24 20:04:26
User: idemal
Functions: tee
Tags: vim sudo tee

Write a file you edited in Vim but that you do not have the permissions to write to (unless you use sudo.) Same as #1204 but without the echo to stdout that I find annoying.

spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://www.google.com/tbproxy/spell|sed -n '/s="[0-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}'|tee >(grep -Eq '.*'||echo -e "OK");}
2010-02-17 08:20:48
User: eightmillion
Functions: echo grep sed tee

I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this:

spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *\(.*\)/Suggestions: \1\n/g;p}';}
find / -name *.conf | tee salida
dd if=/dev/sda | tee >(dd of=/dev/sdb) | dd of=/dev/sdc
2009-12-11 17:34:38
User: nerd65536
Functions: dd tee
Tags: bash tee dd pipe root

If you have some drive imaging to do, you can boot into any liveCD and use a commodity machine. The drives will be written in parallel.

To improve efficiency, specify a larger block size in dd:

dd if=/dev/sda bs=64k | tee >(dd of=/dev/sdb bs=64k) | dd of=/dev/sdc bs=64k

To image more drives , insert them as additional arguments to tee:

dd if=/dev/sda | tee >(dd of=/dev/sdb) >(dd of=/dev/sdc) >(dd of=/dev/sdd) | dd of=/dev/sde
xkcd(){ wget -qO- http://xkcd.com/|tee >(feh $(grep -Po '(?<=")http://imgs[^/]+/comics/[^"]+\.\w{3}'))|grep -Po '(?<=(\w{3})" title=").*(?=" alt)';}
2009-11-27 09:11:47
User: eightmillion
Functions: grep tee wget

This function displays the latest comic from xkcd.com. One of the best things about xkcd is the title text when you hover over the comic, so this function also displays that after you close the comic.

To get a random xkcd comic, I also use the following:

xkcdrandom(){ wget -qO- dynamic.xkcd.com/comic/random|tee >(feh $(grep -Po '(?<=")http://imgs[^/]+/comics/[^"]+\.\w{3}'))|grep -Po '(?<=(\w{3})" title=").*(?=" alt)';}
cat /path/to/some/file.txt | tee /dev/pts/0 | wc -l
2009-11-07 22:24:28
User: atoponce
Functions: cat tee wc
Tags: tee

This is a cool trick to view the contents of the file on /dev/pts/0 (or whatever terminal you're using), and also send the contents of that file to another program by way of an unnamed pipe. All the while, you've not bothered saving any extra data to disk, like you might be tempted to do with sed or grep to filter output.

sqlite3 mydb.sqlite3 '.dump' | grep -vE '^(BEGIN|COMMIT|CREATE|DELETE)|"sqlite_sequence"' | sed -r 's/"([^"]+)"/`\1`/' | tee mydb.sql | mysql -p mydb
2009-10-02 14:40:51
User: mislav
Functions: grep sed tee
Tags: mysql sqlite dump

Filters out all non-insert SQL operations (we couldn't filter out only lines starting with "INSERT" because inserts can span multiple lines), quotes table names with backticks, saves dump to a file and pipes it straight to mysql.

This transfers only data--it expects your schema is already in place. In Ruby on Rails, you can easily recreate the schema in MySQL with "rake db:schema:load RAILS_ENV=production".

echo "blacklist pcspkr"|sudo tee -a /etc/modprobe.d/blacklist.conf
2009-09-27 11:42:47
User: sliceoflinux
Functions: echo sudo tee

This command will disable the beep sound from the PC speaker.