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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 tail from sorted by
Terminal - Commands using tail - 232 results
curl -s kernel.org | grep '<strong>' | head -3 | tail -1 | cut -d'>' -f3 | cut -d'<' -f1
cp $(find /media/ -type f -name "*.wav" -printf "%T@ %h/%f\n" | sort | tail -1 | awk '{ print $2 }') .
2012-06-01 12:45:43
User: hamoid
Functions: awk cp find sort tail

Watch out if you have several USB drives plugged in: it scans the whole /media/ folder !!! You can replace /media/ by the path of a specific USB drive (something like /media/F77A-530B/)

I use a sound recorder and I want to plug the recorder and grab the most recent sound.

That's what this command does.

Use mv instead of cp to move instead of copy.

Change *.wav to the required file type.

ls -l| sort +4n|tail -1| awk '{print $NF}'
tail -F /var/log/apache2/access.log | pv -N RAW -lc 1>/dev/null
2012-05-18 17:19:33
User: rex
Functions: tail

Great easy way to look at line rates for your server

Good to 30k-60k Lines Per second.

tail -F /var/log/nginx/access.log | python -c 'exec("import sys,time\nl=0\ne=int(time.time())\nfor line in sys.stdin:\n\tt = int(time.time())\n\tl += 1\n\tif t > e:\n\t\te = t\n\t\tprint l\n\t\tl = 0")'
2012-05-15 21:56:46
User: pykler
Functions: python tail

Realtime lines per second in a log file using python ... identical to perl version, except python is much better :)

cal 04 2012 | awk 'NF <= 7 { print $7 }' | grep -v "^$" | tail -1
2012-05-03 16:57:45
User: javidjamae
Functions: awk cal grep tail

This is a little trickier than finding the last Sunday, because you know the last Sunday is in the first position of the last line. The trick is to use the NF less than or equal to 7 so it picks up all the lines then grep out any empty lines.

mplayer <(tail -fc +0 <filename>)
2012-04-30 07:28:42
User: gtmanfred
Functions: tail

It will just start playing and will not stop at the point that it has downloaded up to when the video starts

tail() { thbin="/usr/bin/tail"; if [ "${1:0:1}" != "-" ]; then fc=$(($#==0?1:$#)); lpf="$((($LINES - 3 - 2 * $fc) / $fc))"; lpf="$(($lpf<1?2:$lpf))"; [ $fc -eq 1 ] && $thbin -n $lpf "$@" | /usr/bin/fold -w $COLUMNS | $thbin -n $lpf || $thbin -n $lpf...
2012-03-23 19:00:30
User: fpunktk
Functions: tail
tail() { thbin="/usr/bin/tail"; if [ "${1:0:1}" != "-" ]; then fc=$(($#==0?1:$#)); lpf="$((($LINES - 3 - 2 * $fc) / $fc))"; lpf="$(($lpf<1?2:$lpf))"; [ $fc -eq 1 ] && $thbin -n $lpf "$@" | /usr/bin/fold -w $COLUMNS | $thbin -n $lpf || $thbin -n $lpf "$@"; else $thbin "$@"; fi; unset lpf fc thbin; }

This is a function that implements an improved version of tail. It tries to limit the number of lines so that the screen is filled completely. It works with pipes, single and multiple files. If you add different options to tail, they will overwrite the settings from the function.

It doesn't work very well when too many files (with wrapped lines) are specified.

Its optimised for my three-line prompt.

It also works for head. Just s/tail/head/g

Don't set 'thbin="tail"', this might lead to a forkbomb.

while [ 1 ]; do tail /var/log/httpd/error_log; sleep 2; clear; done
git-random(){ gitRan=$(curl -L -s http://whatthecommit.com/ |grep -A 1 "\"c" |tail -1 |sed 's/<p>//'); git commit -m "$gitRan"; }
2012-03-07 22:25:14
Functions: grep sed tail

Put in your path (.bashrc or similar).

Then instead of running '$ git-commit -m ' use '$ git-random'

tail -f file | ts '%H:%M:%.S'
2012-03-02 11:15:29
User: Vagrant
Functions: file tail

Uses the command ts in order to add a timestamp on each line. This command is provided in the moreutils package on Debian, and you may need libtime-duration-perl to be able to format the date.

tail -f production.log | perl -ne 'if (/^Completed.in.(\d+)/){$d = int($1/1000);print "\n";$f{$d}++;for $t (sort(keys(%f))){print $t."s: ".$f{$t}."\n"}}'
2012-02-23 14:37:33
User: theist
Functions: perl tail

Commandline perl filter for, using a production.log from a rails app, display on realtime the count of requests grouped by "seconds to complete" (gross round, but fair enough for an oneliner) :)

identify image.jpg |grep -o "[[:digit:]]*x[[:digit:]]*" |tail -1
tail -f file | while read; do echo "$(date +%T.%N) $REPLY"; done
TOTAL_RAM=`free | head -n 2 | tail -n 1 | awk '{ print $2 }'`; PROC_RSS=`ps axo rss,comm | grep [h]ttpd | awk '{ TOTAL += $1 } END { print TOTAL }'`; PROC_PCT=`echo "scale=4; ( $PROC_RSS/$TOTAL_RAM ) * 100" | bc`; echo "RAM Used by HTTP: $PROC_PCT%"
while true; do curl -s http://sensiblepassword.com/?harder=1 | tail -n 15 | head -n 1 | sed 's;<br/>;;' | cut -c 5- | cb; sleep 1; done
2012-01-30 20:52:14
User: supervacuo
Functions: cut head sed sleep tail

Use the excellent sensiblepasswords.com to a generate random (yet easy-to-remember) password every second, and copy it to the clipboard. Useful for generating a list of passwords and pasting them into a spreadsheet.

This script uses "madebynathan"'s "cb" function (http://madebynathan.com/2011/10/04/a-nicer-way-to-use-xclip/); you could also replace "cb" with

xclip -selection c

Remove "while true; do" and "; done" to generate and copy only 1 password.

tail -f to.log | colorize.pl +l10:".*" &
2012-01-20 21:46:47
User: peter4512
Functions: tail
Tags: perl

(follow with next command)

tail -f from.log | colorize.pl +l20:".*" &

Use with http://www.commandlinefu.com/commands/view/10031/intercept-monitor-and-manipulate-a-tcp-connection. - can use to view output of tees that send traffic to files - output will be interwoven with red for sent traffic and green for received.

get colorize.pl from http://www.flinkmann.de/71-1-Colorizepl.html

ssh remotebox tail -f /var/log/remotelog
find /usr/include/ -name '*.[c|h]pp' -o -name '*.[ch]' -print0 | xargs -0 wc -l | tail -1
script -f /tmp/foo; tail -f /tmp/foo
2011-11-22 15:16:08
Functions: script tail
Tags: script tail -f

script -f /tmp/foo will place all output of the terminal, including carriage returns, to a file. This file can be tail dash-eff'ed by one or more other terminals to display the information of the main terminal. Good way to share one's screen on short notice.

Note: This produces a very accurate output, but that includes depending on the size of your terminal to be the same. You can clear screens or even resize the terminal for others using this function; I use it in conjunction with the "mid" command in my list.

ps -p pid -o logname |tail -1
expandurl() { curl -sIL $1 2>&1 | awk '/^Location/ {print $2}' | tail -n1; }
2011-10-19 01:35:33
Functions: awk tail
Tags: curl

This shell function uses curl(1) as it is more portable than wget(1) across Unices, to show what site a shortened URL is pointing to, even if there are many nested shortened URLs. It is a refinement to www.commandlinefu.com/commands/view/9515/expand-shortened-urls to make it better for use in scripts. Only displays final result.

expandurl http://t.co/LDWqmtDM
ls -lFart |tail -n1
2011-10-17 19:49:14
User: jambino
Functions: ls tail
Tags: tail pipe ls

List all files in a directory in reverse order by modified timestamp. When piped through tail the user will see the most recent file name.

lastfile () { find ${1:-.} -maxdepth 1 -type f -printf "%T+ %p\n" | sort -n | tail -n1 | sed 's/[^[:space:]]\+ //'; }
2011-10-17 16:08:02
User: bartonski
Functions: find sed sort tail

Takes a directory name as an argument (defaults to current directory if no arguments are given). Prints the newest file in the directory.

:|dd of=./ssss.txt seek=1 bs=$(($(stat -c%s ./ssss.txt)-$(tail -n 2 ./ssss.txt|wc -c)))
2011-10-17 07:53:00
User: ri0day
Functions: dd stat tail wc

new way to replace text file with dd,faster than head,sed,awk if you do this with big file