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Commands using tail from sorted by
Terminal - Commands using tail - 225 results
while (true); do clear; uname -n; echo ""; df -h /; echo ""; tail -5 /var/log/auth.log; echo ""; vmstat 1 5; sleep 15; done
2010-08-23 04:37:58
User: roknir
Functions: df echo sleep tail uname vmstat
1

You can use this one-liner for a quick and dirty (more customizable) alternative to the watch command. The keys to making this work: everything exists in an infinite loop; the loop starts with a clear; the loop ends with a sleep. Enter whatever you'd like to keep an eye on in the middle.

tail -f /var/log/system.log | colorizer
git log --pretty=format:%H | tail -1
2010-08-17 13:47:42
Functions: tail
Tags: git commit
1

git log --format=%H | tail -1 doesn't work anymore

rsync -av --link-dest=$(ls -1d /backup/*/ | tail -1) /data/ /backup/$(date +%Y%m%d%H%M)/
2010-08-05 19:36:24
User: dooblem
Functions: date ls rsync tail
Tags: backup rsync
1

'data' is the directory to backup, 'backup' is directory to store snapshots.

Backup files on a regular basis using hard links. Very efficient, quick. Backup data is directly available.

Same as explained here :

http://blog.interlinked.org/tutorials/rsync_time_machine.html

in one line.

Using du to check the size of your backups, the first backup counts for all the space, and other backups only files that have changed.

sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'|xargs -r tail -f
2010-07-30 18:20:00
User: vutcovici
Functions: echo eval grep ls sed sudo tail xargs
-1

Tail all logs that are opened by all java processes. This is helpful when you are on a new environment and you do not know where the logs are located. Instead of java you can put any process name. This command does work only for Linux.

The list of all log files opened by java process:

sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'
git log --format=%H | tail -1
2010-07-20 08:12:05
User: l0b0
Functions: tail
Tags: git commit
0

Can anyone make a shorter one?

This doesn't work:

git log --reverse -1 --format=%H
url=http://www.youtube.com/watch?v=V5bYDhZBFLA; youtube-dl -b $url; mplayer $(ls ${url##*=}*| tail -n1) -ss 00:57 -endpos 10 -vo gif89a:fps=5:output=output.gif -vf scale=400:300 -nosound
2010-07-18 02:11:39
User: zed
Functions: ls tail
12

requires "youtube-dl" -- sure you can do this with wget and some more obscurity but why waste your time when this great tool is available?

the guts consist of mplayer converting a video to a gif -- study this command and read the man page for more information

mplayer video.flv -ss 00:23 -endpos 6 -vo gif89a:fps=5:output=output.gif -vf scale=400:300 -nosound

generates a 6 second gif starting at 23 seconds of play time at 5 fps and a scale of 400x300

start time (-ss)/end time (-endpos) formats: 00:00:00.000

end time should be relative to start time, not absolute. i.e. -endpos 5 == seconds after 0:42 = 0:47 end point

play with fps and scale for lower gif sizes

the subshell is a solution for the -b flag on youtube-dl which downloads the best quality video, sometimes, which can be various video formats $(ls ${url##*=}*| tail -n1)

while (( 1==1 )); do du -c . >> output.log; sleep 2; done; tail -f output.log
2010-07-12 17:23:45
User: aceiro
Functions: du sleep tail
-5

this command shows the space used in postgres directory.

tail -n +4 | head -n 1
head -n X | tail -n 1
2010-07-08 22:06:39
User: infinull
Functions: head tail
-1

using tail first won't do it because tail counts from the bottom of the file. You could do it this way but I don't suggest it

tail -n 4 | head -n 1
2010-07-08 19:50:06
User: puddy
Functions: head tail
-7

tail -n X | head -n 1

prints a specific line, where X is the line number

IFS=`echo -en "\n\b"`; for i in $(curl http://feeds.digg.com/digg/container/technology/popular.rss | grep '<title>' | sed -e 's#<[^>]*>##g' | tail -n10); do echo $i; echo $i | sed 's/^/Did you hear about /g' | say; sleep 30; done
2010-06-07 22:16:19
User: echosedawk
Functions: echo grep sed sleep tail
Tags: bash sed curl osx
-2

Instead of having someone else read you the Digg headlines, Have OSX do it. Requires Curl+Sed+Say. This could probably be easily modified to use espeak for Linux.

tune2fs -l $(df -P / | tail -n1 | cut -d' ' -f1 ) | grep 'Filesystem created:'
diff <(tail -10 file1) <(tail -10 file2)
tail -fs 1 somefile
2010-05-18 23:42:35
User: ppaschka
Functions: tail
9

The -s option allows you to specify the update interval

tail -n2000 /var/www/domains/*/*/logs/access_log | awk '{print $1}' | sort | uniq -c | sort -n | awk '{ if ($1 > 20)print $1,$2}'
mplayer http://minnesota.publicradio.org/tools/play/streams/the_current.pls < /dev/null | grep --line-buffered "StreamTitle='.*S" -o | grep --line-buffered "'.*'" -o > mus & tail -n0 -f mus | while read line; do notify-send "Music Change" "$line";done
2010-05-09 17:51:40
User: spiffwalker
Functions: grep read tail
7

Plays the mp3 stream of The Current as a background job. When you are done run:

fg %1

then to exit

Quite possible with Growl for mac I'd guess, although have not tried.

Libnotify needed for notification, stream will still work otherwise

tail -f error_log | nc -l 1234
2010-05-07 18:14:04
User: zlemini
Functions: tail
3

Netcat is used to serve a log-file over a network on port 1234.

Point a browser to the specified server/port combo to view log-file updates in real-time.

/etc/init.d/cron restart && tail -100 /var/log/syslog
2010-05-05 09:56:30
User: root
Functions: tail
-7

Debian-specific but very useful as cron files are prone to very subtle gotchas

shopt -s extglob; for f in *.ttf *.TTF; do g=$(showttf "$f" 2>/dev/null | grep -A1 "language=0.*FullName" | tail -1 | rev | cut -f1 | rev); g=${g##+( )}; mv -i "$f" "$g".ttf; done
2

Just a quick hack to give reasonable filenames to TrueType and OpenType fonts.

I'd accumulated a big bunch of bizarrely and inconsistently named font files in my ~/.fonts directory. I wanted to copy some, but not all, of them over to my new machine, but I had no idea what many of them were. This script renames .ttf files based on the name embedded inside the font. It will also work for .otf files, but make sure you change the mv part so it gives them the proper extension.

REQUIREMENTS: Bash (for extended pattern globbing), showttf (Debian has it in the fontforge-extras package), GNU grep (for context), and rev (because it's hilarious).

BUGS: Well, like I said, this is a quick hack. It grew piece by piece on the command line. I only needed to do this once and spent hardly any time on it, so it's a bit goofy. For example, I find 'rev | cut -f1 | rev' pleasantly amusing --- it seems so clearly wrong, and yet it works to print the last argument. I think flexibility in expressiveness like this is part of the beauty of Unix shell scripting. One-off tasks can be be written quickly, built-up as a person is "thinking aloud" at the command line. That's why Unix is such a huge boost to productivity: it allows each person to think their own way instead of enforcing some "right way".

On a tangent: One of the things I wish commandlinefu would show is the command line HISTORY of the person as they developed the script. I think it's that conversation between programmer and computer, as the pipeline is built piece-by-piece, that is the more valuable lesson than any canned script.

tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log
2010-04-29 21:23:46
User: dooblem
Functions: kill sleep tail wc
Tags: tail kill wc sleep
1

Another way of counting the line output of tail over 10s not requiring pv.

Cut to have the average per second rate :

tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2

You can also enclose it in a loop and send stderr to /dev/null :

while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

tail -f access.log | pv -l -i10 -r >/dev/null
2010-04-29 21:02:01
User: dooblem
Functions: tail
Tags: tail pv
6

Displays the realtime line output rate of a logfile.

-l tels pv to count lines

-i to refresh every 10 seconds

-l option is not in old versions of pv. If the remote system has an old pv version:

ssh tail -f /var/log/apache2/access.log | pv -l -i10 -r >/dev/null

tail -f access_log | cut -c2-21 | uniq -c
2010-04-29 11:16:54
User: buzzy
Functions: cut tail uniq
Tags: uniq tail cut
4

Change the cut range for hits per 10 sec, minute and so on... Grep can be used to filter on url or source IP.

for i in emerg alert crit error warn ; do awk '$6 ~ /^\['$i'/ {print substr($0, index($0,$6)) }' error_log | sort | uniq -c | sort -n | tail -1; done
2010-04-15 21:47:18
User: zlemini
Functions: awk sort tail uniq
4

This searches the Apache error_log for each of the 5 most significant Apache error levels, if any are found the date is then cut from the output in order to sort then print the most common occurrence of each error.

tail /var/log/emerge.log | awk -F: '{print strftime("%Y%m%d %X %Z", $1),$2}'