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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using tee from sorted by
Terminal - Commands using tee - 90 results
echo mem|sudo tee /sys/power/state
sudo sync && sudo echo 3 | sudo tee /proc/sys/vm/drop_caches
2012-03-17 08:27:58
User: StephenJudge
Functions: echo sudo sync tee
Tags: memory cache

"That's it. Not much to see here. The first command writes any cache data that hasn't been written to the disk out to the disk. The second command tells the kernel to drop what's cached. Not much to it. This invalidates the write cache as well as the read cache, which is why we have the sync command first. Supposedly, it is possible to have some cached write data never make it to disk, so use it with caution, and NEVER do it on a production server. You could ... but why take the risk?

As long as you are running a post 2.6.16 kernel,..."

Source: http://ubuntuforums.org/showpost.php?p=3621283&postcount=1

curl -s ifconfig.me|tee >(xargs geoiplookup)
2012-02-09 20:30:26
Functions: tee xargs
Tags: tee curl geoip

Show external IP and geolocation information.

Primary feature is the use of tee to echo IP _and_ send to geoiplookup command...Use IP as input for as many commands as you want with more >( [command] )

Thanks to http://www.commandlinefu.com/commands/view/6334/

Requires MaxMind DB and geoiplookup tool.

Sample output has IP obfuscated on first line, lines 2-4 from having MaxMind Country && MaxMind City DBs installed

!w sudo tee %
command > >(tee stdout.log) 2> >(tee stderr.log >&2)
sync && echo 3 | sudo tee /proc/sys/vm/drop_caches
command W :execute ':silent w !sudo tee % > /dev/null' | :edit!
2011-10-06 20:37:54
Functions: command tee
Tags: vim sudo tee

Calls sudo tee like all the other lines, but also automatically reloads the file.

Optionally you can add

command Wq :execute ':W' | :q


command WQ :Wq

to make quitting easier

sudo find / -type f | perl -MFile::Basename -ne '$counts{dirname($_)}++; END { foreach $d (sort keys %counts) {printf("%d\t%s\n",$counts{$d},$d);} }'|sort -rn | tee /tmp/sortedfilecount.out | head
2011-09-14 19:41:19
User: tamouse
Functions: find perl sort sudo tee

Find which directories on your system contain a lot of files.

Edit: much shorter and betterer with -n switch.

(set -e; while true; do TEST_COMMAND; done) | tee log
2011-09-06 12:29:11
User: wipu
Functions: set tee
Tags: tee while set

If you need to fix a randomly failing test (race condition), you need to run it until you get that hard-to-reproduce failure.

find . -type f | xargs grep -n "Old Text" | tee filesChanged.txt | sed 's/:.*$//' | xargs sed -i 's/Old Text/New Text/g
:%!sudo tee %
2011-06-17 07:16:23
User: antone
Functions: tee
Tags: vim sudo tee

probably just like 1204, but uses tee as a filter (+ I actually understand how this one works)

echo "GRUB_INIT_TUNE=\"480 440 4 440 4 440 4 349 3 523 1 440 4 349 3 523 1 440 8 659 4 659 4 659 4 698 3 523 1 415 4 349 3 523 1 440 8"\"" | sudo tee -a /etc/default/grub > /dev/null && sudo update-grub
find . -name "*.png" | tee images.txt | grep book
2011-06-02 23:55:50
Functions: find grep tee

You can find every file with png extension and redirect its output to file. Later you can find a string inside the file.

for i in $(find . -name *md5checksum_file* | sed 's/\(\.\/.*\)md5checksum_file.txt/\1/'); do cd "$i"; md5sum -c "md5checksum_file.txt"; cd -; done | tee ~/checksum_results.txt | grep -v "<current directory>"
2011-05-17 01:08:44
User: gocoogs
Functions: cd find grep md5sum sed tee

extracts path to each md5 checksum file, then, for each path, cd to it, check the md5sum, then cd - to toggle back to the starting directory. greps at the end to remove cd chattering on about the current directory.

nohup cat /dev/ttyS0 | tee -a llamadas.db&
mkdir copy{1,2}; gzip -dc file.tar.gz | tee >( tar x -C copy1/ ) | tar x -C copy2/
2011-04-14 17:02:05
User: depesz
Functions: gzip mkdir tar tee
Tags: bash tee tar

Sometimes you might need to have two copies of data that is in tar. You might unpack, and then copy, but if IO is slow, you might lower it by automatically writing it twice (or more times)

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.