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Commands using tail from sorted by
Terminal - Commands using tail - 219 results
end_w_nl() { [[ $(tail -c1 $1 | xxd -ps) == 0a ]] }
2012-09-18 20:11:29
User: xro
Functions: tail
Tags: tail xxd zsh
0
Up
Down
Function to check whether a regular file ends with a newline
end_w_nl filename

will check if the last byte of filename is a unix newline character. tail -c1 yields the file's last byte and xxd converts it to hex format.

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tail -n +2 foo.txt
2012-09-13 20:54:36
User: kaushalmehra
Functions: tail
Tags: unix
3
Up
Down
Deleting / Ignoring lines from the top of a file

Output lines starting at line 2.

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ls -rt | tail -n 1
2012-09-06 07:07:35
User: m0rf
Functions: ls tail
0
Up
Down
Find latest file in a directory
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lsmod | tail -n +2 | cut -d' ' -f1 | xargs modinfo | egrep '^file|^desc|^dep' | sed -e'/^dep/s/$/\n/g'
2012-09-03 17:59:49
User: vlaad
Functions: cut egrep lsmod modinfo sed tail xargs
Tags: xargs lsmod modinfo
0
Up
Down
Short Information about loaded kernel modules
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tail -f /proc/partitions
2012-08-17 05:57:12
User: huazhihao
Functions: tail
-4
Up
Down
detect partitions
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ifconfig | grep "inet" | tail -1 | awk '{print $2}'
2012-07-13 01:27:59
User: wotan
Functions: awk grep ifconfig tail
Tags: ifconfig
0
Up
Down
Get the IP address

more variety

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systemctl --failed | head -n -6 | tail -n -1
2012-07-11 22:31:46
User: corpix
Functions: head tail
0
Up
Down
Print failed units in systemd
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find . -name "fullcalib4.csv" -exec tail -n1 \{\} \; >>all.csv
2012-06-27 16:12:47
User: kaplan2539
Functions: find tail
0
Up
Down
collect fullcalib data
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amixer -c 0 set Master toggle | tail -1 | awk '{print $4}' | sed "s/[^0-9]//g" ; amixer -c 0 set Speaker toggle >/dev/null; amixer -c 0 set Front toggle >/dev/null
2012-06-26 21:18:07
User: dtsip
Functions: amixer awk sed set tail
0
Up
Down
Unmuting master channel, printing only percent value, while suppressing other outputs
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tail -f logfile | logtop
2012-06-24 19:18:30
User: Sizeof
Functions: tail
Tags: tail
-1
Up
Down
Realtime lines per second in a log file

logtop show number of lines per second, also classify them so you can show a "top" of every aspect of your logfile :

tail -f access.log | awk '{print $1; fflush();}' | logtop

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curl -s kernel.org | grep '<strong>' | head -3 | tail -1 | cut -d'>' -f3 | cut -d'<' -f1
2012-06-15 21:28:42
User: mdix
Functions: cut grep head tail
0
Up
Down
Get current stable kernel version string from kernel.org
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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
Tags: newest file most recent file
0
Up
Down
Copy the most recent wav file from /media/ to the current folder

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.

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ls -l| sort +4n|tail -1| awk '{print $NF}'
2012-05-25 06:35:39
User: pritishunix
Functions: awk ls sort tail
0
Up
Down
Get the file name having biggest size in directory.
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tail -F /var/log/apache2/access.log | pv -N RAW -lc 1>/dev/null
2012-05-18 17:19:33
User: rex
Functions: tail
0
Up
Down
Log Lines Per Second apache, nginx, haproxy and/or squid

Great easy way to look at line rates for your server

Good to 30k-60k Lines Per second.

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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
Tags: tail python accesslog
0
Up
Down
Realtime lines per second in a log file

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

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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
Tags: Date manipulation awk tail grep date dates cal
-2
Up
Down
Get the date for the last Saturday of a given month

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.

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mplayer <(tail -fc +0 <filename>)
2012-04-30 07:28:42
User: gtmanfred
Functions: tail
Tags: mplayer tail -f
0
Up
Down
don't have video stop at EOF while it is downloading

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

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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 $lpf...
2012-03-23 19:00:30
User: fpunktk
Functions: tail
Tags: bash tail variable
-1
Up
Down
a tail function for automatic smart output
tail() { thbin="/usr/bin/tail"; if [ "${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.

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while [ 1 ]; do tail /var/log/httpd/error_log; sleep 2; clear; done
2012-03-09 17:10:40
User: wildtype
Functions: sleep tail
Tags: httpd
0
Up
Down
Continously show httpd's error log
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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
User: unixmonkey32483
Functions: grep sed tail
0
Up
Down
random git-commit message

Put in your path (.bashrc or similar).

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

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tail -f file | ts '%H:%M:%.S'
2012-03-02 11:15:29
User: Vagrant
Functions: file tail
1
Up
Down
Annotate tail -f with timestamps

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.

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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
Tags: perl log rails ruby filter tail -f
0
Up
Down
filter rails log to count requests sliced in seconds

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) :)

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identify image.jpg |grep -o "[[:digit:]]*x[[:digit:]]*" |tail -1
2012-02-19 06:49:38
User: totti
Functions: grep tail
Tags: ImageMagick resolution image
0
Up
Down
Resolution of a image
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tail -f file | while read; do echo "$(date +%T.%N) $REPLY"; done
2012-02-18 17:22:53
User: yoyoyojomo
Functions: echo file tail
19
Up
Down
Annotate tail -f with timestamps
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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%"
2012-02-03 16:10:36
User: 0disse0
Functions: awk echo grep head tail
Tags: memory usage process
0
Up
Down
display memory usage of a process

page where I got inspiration:

http://www.commandlinefu.com/commands/view/5473/get-acurate-memory-usage-of-a-process-in-megabytes

and

http://www.commandlinefu.com/commands/view/10022/display-the-top-10-running-processes-sorted-by-memory-usage

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