Commands using tail (253)


  • 0
    curl --silent http://www.dudalibre.com/gnulinuxcounter?lang=en | grep users | head -2 | tail -1 | sed 's/.*<strong>//g' | sed 's/<\/strong>.*//g'
    hunterm · 2010-10-07 04:12:45 0
  • Tail curren postfix maillog.


    1
    tail -f `ls -alst /var/log/maillog* | awk '{print $10} NR>0{exit};0'` | grep "criteria"
    ozgurkuru · 2010-09-01 15:15:15 0
  • tail -c 1 "$1" returns the last byte in the file. Command substitution deletes any trailing newlines, so if the file ended in a newline $(tail -c 1 "$1") is now empty, and the -z test succeeds. However, $a will also be empty for an empty file, so we add -s "$1" to check that the file has a size greater than zero. Finally, -f "$1" checks that the file is a regular file -- not a directory or a socket, etc. Show Sample Output


    1
    endnl () { [[ -f "$1" && -s "$1" && -z $(tail -c 1 "$1") ]]; }
    quintic · 2010-08-25 12:06:10 0
  • 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. Show Sample Output


    1
    while (true); do clear; uname -n; echo ""; df -h /; echo ""; tail -5 /var/log/auth.log; echo ""; vmstat 1 5; sleep 15; done
    roknir · 2010-08-23 04:37:58 0
  • Download colorizer by @raszi @ http://github.com/raszi/colorize


    1
    tail -f /var/log/system.log | colorizer
    Sadus · 2010-08-20 11:30:03 0
  • git log --format=%H | tail -1 doesn't work anymore Show Sample Output


    1
    git log --pretty=format:%H | tail -1
    unixmonkey6264 · 2010-08-17 13:47:42 0
  • '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. Show Sample Output


    1
    rsync -av --link-dest=$(ls -1d /backup/*/ | tail -1) /data/ /backup/$(date +%Y%m%d%H%M)/
    dooblem · 2010-08-05 19:36:24 0
  • 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'


    -1
    sudo ls -l $(eval echo "/proc/{$(echo $(pgrep java)|sed 's/ /,/')}/fd/")|grep log|sed 's/[^/]* //g'|xargs -r tail -f
    vutcovici · 2010-07-30 18:20:00 0
  • Can anyone make a shorter one? This doesn't work: git log --reverse -1 --format=%H Show Sample Output


    0
    git log --format=%H | tail -1
    l0b0 · 2010-07-20 08:12:05 0
  • 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) Show Sample Output


    12
    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
    zed · 2010-07-18 02:11:39 1
  • this command shows the space used in postgres directory. Show Sample Output


    -5
    while (( 1==1 )); do du -c . >> output.log; sleep 2; done; tail -f output.log
    aceiro · 2010-07-12 17:23:45 0

  • -5
    tail -n +4 | head -n 1
    unixmonkey10745 · 2010-07-09 12:10:03 0
  • 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


    -1
    head -n X | tail -n 1
    infinull · 2010-07-08 22:06:39 1
  • tail -n X | head -n 1 prints a specific line, where X is the line number


    -7
    tail -n 4 | head -n 1
    puddy · 2010-07-08 19:50:06 0
  • 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.


    -2
    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
    echosedawk · 2010-06-07 22:16:19 1

  • -3
    tune2fs -l $(df -P / | tail -n1 | cut -d' ' -f1 ) | grep 'Filesystem created:'
    christian773 · 2010-05-29 08:15:25 1
  • This only works in bash


    3
    diff <(tail -10 file1) <(tail -10 file2)
    elofland · 2010-05-20 14:04:17 2
  • The -s option allows you to specify the update interval


    9
    tail -fs 1 somefile
    ppaschka · 2010-05-18 23:42:35 1

  • 4
    tail -n2000 /var/www/domains/*/*/logs/access_log | awk '{print $1}' | sort | uniq -c | sort -n | awk '{ if ($1 > 20)print $1,$2}'
    allrightname · 2010-05-10 19:08:37 0
  • 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


    7
    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
    spiffwalker · 2010-05-09 17:51:40 0
  • 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.


    3
    tail -f error_log | nc -l 1234
    zlemini · 2010-05-07 18:14:04 5
  • Debian-specific but very useful as cron files are prone to very subtle gotchas


    -7
    /etc/init.d/cron restart && tail -100 /var/log/syslog
    root · 2010-05-05 09:56:30 0
  • 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. Show Sample Output


    2
    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
    hackerb9 · 2010-04-30 09:46:45 0
  • 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


    1
    tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log
    dooblem · 2010-04-29 21:23:46 0
  • 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


    9
    tail -f access.log | pv -l -i10 -r >/dev/null
    dooblem · 2010-04-29 21:02:01 0
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