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Commands using tail from sorted by
Terminal - Commands using tail - 239 results
tail -f file | while read line; do printf "$(date -u '+%F %T%z')\t$line\n"; done
2010-11-24 05:50:12
User: derekschrock
Functions: file printf read tail
Tags: tail date

Should be a bit more portable since echo -e/n and date's -Ins are not.

tail -f file | while read line; do echo -n $(date -u -Ins); echo -e "\t$line"; done
2010-11-19 10:01:57
User: hfs
Functions: date echo file read tail
Tags: tail date

This is useful when watching a log file that does not contain timestamps itself.

If the file already has content when starting the command, the first lines will have the "wrong" timestamp when the command was started and not when the lines were originally written.

history | awk '{print $2,$3}' | sed s/sudo// | awk '{print $1}' | awk 'BEGIN {FS="|"}{print $1}' | sort | uniq -c | sort -n | tail | sort -nr
2010-11-17 12:15:04
User: b_t
Functions: awk sed sort tail uniq

Your version works fine except for someone who's interested in commands 'sudo' was prefixed to

i.e. in your command, use of sudo appears as number of times sudo was used.

Slight variation in my command peeks into what commands sudo was used for and counts the command

(ignores 'sudo')

history | awk '{print $2}' | awk 'BEGIN {FS="|"}{print $1}' | sort | uniq -c | sort -n | tail | sort -nr
grep 'model\|MHz' /proc/cpuinfo |tail -n 2
find /home/ -type f -exec du {} \; 2>/dev/null | sort -n | tail -n 10 | xargs -n 1 du -h 2>/dev/null
2010-11-10 07:24:17
User: mxc
Functions: du find sort tail xargs
Tags: disk usage

This combines the above two command into one. Note that you can leave off the last two commands and simply run the command as

"find /home/ -type f -exec du {} \; 2>/dev/null | sort -n | tail -n 10"

The last two commands above just convert the output into human readable format.

find / -type f -size +100M -exec du {} \; | sort -n | tail -10 | cut -f 2
find / -type f 2>/dev/null | xargs du 2>/dev/null | sort -n | tail -n 10 | cut -f 2 | xargs -n 1 du -h
2010-11-09 13:45:11
User: mxc
Functions: cut du find sort tail xargs
Tags: disk usage

Often you need to find the files that are taking up the most disk space in order to free up space asap. This script can be run on the enitre filesystem as root or on a home directory to find the largest files.

IP=$(nslookup `hostname` | grep -i address | awk -F" " '{print $2}' | awk -F# '{print $1}' | tail -n 1 ); R=3$((RANDOM%6 + 1)); PS1="\n\[\033[1;37m\]\u@\[\033[1;$R""m\]\h^$IP:\[\033[1;37m\]\w\$\[\033[0m\] "
2010-10-20 07:29:14
User: rubo77
Functions: awk grep nslookup tail

this adds a random color to your prompt and the external ip.

useful if you are using multiple mashines with the same hostname.

s=`head -$i fileName | tail -1`
tail -f /var/log/messages | while read line; do accu="$line"; while read -t 1 more; do accu=`echo -e "$accu\n$more"`; done; notify-send "Syslog" "$accu"; done
2010-10-10 16:28:08
User: hfs
Functions: read tail

The given example collects output of the tail command: Whenever a line is emitted, further lines are collected, until no more output comes for one second. This group of lines is then sent as notification to the user.

You can test the example with

logger "First group"; sleep 1; logger "Second"; logger "group"
curl --silent http://www.dudalibre.com/gnulinuxcounter?lang=en | grep users | head -2 | tail -1 | sed 's/.*<strong>//g' | sed 's/<\/strong>.*//g'
tail -f `ls -alst /var/log/maillog* | awk '{print $10} NR>0{exit};0'` | grep "criteria"
endnl () { [[ -f "$1" && -s "$1" && -z $(tail -c 1 "$1") ]]; }
2010-08-25 12:06:10
User: quintic
Functions: tail
Tags: tail

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.

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

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

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

'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 :


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

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

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

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

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

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

tail -n X | head -n 1

prints a specific line, where X is the line number