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Commands using tail from sorted by
Terminal - Commands using tail - 236 results
head -$(($RANDOM % $(wc -l < file.txt) +1 )) file.txt | tail -1
tail -F file
2009-07-23 07:37:11
User: recursiverse
Functions: tail
Tags: tail logs
15

If you use 'tail -f foo.txt' and it becomes temporarily moved/deleted (ie: log rolls over) then tail will not pick up on the new foo.txt and simply waits with no output.

'tail -F' allows you to follow the file by it's name, rather than a descriptor. If foo.txt disappears, tail will wait until the filename appears again and then continues tailing.

ls -drt /var/log/* | tail -n5 | xargs sudo tail -n0 -f
2009-07-22 14:44:41
User: kanaka
Functions: ls sudo tail xargs
Tags: bash tail log watch
5

This command finds the 5 (-n5) most frequently updated logs in /var/log, and then does a multifile tail follow of those log files.

Alternately, you can do this to follow a specific list of log files:

sudo tail -n0 -f /var/log/{messages,secure,cron,cups/error_log}

cp `ls -x1tr *.jpg | tail -n 1` newest.jpg
2009-06-17 20:32:04
User: Psychodad
Functions: cp tail
1

search the newest *.jpg in the directory an make a copy to newest.jpg. Just change the extension to search other files. This is usefull eg. if your webcam saves all pictures in a folder and you like the put the last one on your homepage. This works even in a directory with 10000 pictures.

find /var/log -type f -exec file {} \; | grep 'text' | cut -d' ' -f1 | sed -e's/:$//g' | grep -v '[0-9]$' | xargs tail -f
2009-06-03 09:47:08
User: mohan43u
Functions: cut file find grep sed tail xargs
Tags: tail
6

Works in Ubuntu, I hope it will work on all Linux machines. For Unixes, tail should be capable of handling more than one file with '-f' option.

This command line simply take log files which are text files, and not ending with a number, and it will continuously monitor those files.

Putting one alias in .profile will be more useful.

tail -f FILE | perl -pe 's/KEYWORD/\e[1;31;43m$&\e[0m/g'
2009-06-02 21:31:54
User: tuxifier
Functions: perl tail
17

tail with coloured output with the help of perl - need more colours? here is a colour table:

http://www.tuxify.de/?p=23

lynx -source http://www.commandlinefu.com/commands/random | sed 's/<[^>]*>//g' | head -1037 | tail -10 | sed -e 's/^[ \t]*//' | sed '/^$/d' | head -2
F="$HOME/.moz*/fire*/*/session*.js" ; grep -Go 'entries:\[[^]]*' $F | cut -d[ -f2 | while read A ; do echo $A | sed s/url:/\n/g | tail -1 | cut -d\" -f2; done
2009-05-21 21:58:42
User: b2e
Functions: cut echo grep read sed tail
3

Tuned for short command line - you can set the path to sessionstore.js more reliable instead of use asterixes etc.

Usable when you are not at home and really need to get your actual opened tabs on your home computer (via SSH). I am using it from my work if I forgot to bookmark some new interesting webpage, which I have visited at home. Also other way to list tabs when your firefox has crashed (restoring of tabs doesn't work always).

This script includes also tabs which has been closed short time before.

tail -f --retry /var/log/syslog /var/log/auth.log | ccze -A
ps -eo user,pcpu,pmem | tail -n +2 | awk '{num[$1]++; cpu[$1] += $2; mem[$1] += $3} END{printf("NPROC\tUSER\tCPU\tMEM\n"); for (user in cpu) printf("%d\t%s\t%.2f%\t%.2f%\n",num[user], user, cpu[user], mem[user]) }'
function jumpTo { xmms2 jump `xmms2 list | grep -i '$1' | head -n 1 | tail -n 1 | sed -re 's@.+\[(.+)/.+\] (.+)@\1@'`; }
2009-04-10 13:43:57
User: pyrho
Functions: grep head sed tail
Tags: xmms2
1

Usage:

Declare this function in your Shell, then use it like this:

> jumpTo foo

The script will search for the 'foo' pattern in your current xmms2 playlist (artist or songname), and play the first occurence of it !

ps aux | sort +2n | tail -20
2009-03-31 12:03:34
User: dopeman
Functions: ps sort tail
3

This command will show the 20 processes using the most CPU time (hungriest at the bottom).

You can see the 20 most memory intensive processes (hungriest at the bottom) by running:

ps aux | sort +3n | tail -20

Or, run both:

echo "CPU:" && ps aux | sort +2n | tail -20 && echo "Memory:" && ps aux | sort +3n | tail -20
du -xk | sort -n | tail -20
2009-03-30 11:37:43
User: dopeman
Functions: du sort tail
7

This command will tell you the 20 biggest directories starting from your working directory and skips directories on other filesystems. Useful for resolving disk space issues.

while [ 1 ]; do echo -n "`date +%F_%T`" ; vmstat 1 2 | tail -1 ; sleep 4; done
2009-03-26 19:16:55
User: plasticboy
Functions: echo sleep tail vmstat
3

See man vmstat for information about the statistics.

This does the same thing without the timestamp:

vmstat 5
tail -f logfile.log | cut -b 1-80
2009-03-26 18:41:57
User: plasticboy
Functions: cut tail
Tags: tail log
3

This truncates any lines longer than 80 characters. Also useful for looking at different parts of the line, e.g. cut -b 50-100 shows columns 50 through 100.

history | perl -lane '$lsize{$_} = scalar(@F); if($longest<$lsize{$_}) { $longest = $lsize{$_}; print "$_"; };' | tail -n1
INFILE=/path/to/your/backup.img; MOUNTPT=/mnt/foo; PARTITION=1; mount "$INFILE" "$MOUNTPT" -o loop,offset=$[ `/sbin/sfdisk -d "$INFILE" | grep "start=" | head -n $PARTITION | tail -n1 | sed 's/.*start=[ ]*//' | sed 's/,.*//'` * 512 ]
6

Suppose you made a backup of your hard disk with dd:

dd if=/dev/sda of=/mnt/disk/backup.img

This command enables you to mount a partition from inside this image, so you can access your files directly.

Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img).

cat $(ls -tr | tail -1) | awk '{ a[$1] += 1; } END { for(i in a) printf("%d, %s\n", a[i], i ); }' | sort -n | tail -25
2009-03-06 17:50:29
User: oremj
Functions: awk cat ls sort tail
7

This command is much quicker than the alternative of "sort | uniq -c | sort -n".

tail -f *[!.1][!.gz]
2009-03-06 16:24:44
User: piscue
Functions: tail
5

with discard wilcards in bash you can "tail" newer logs files to see what happen, any error, info, warn...

du | sort -n | tail -11 | head
2009-03-04 16:06:34
User: phage
Functions: du sort tail
-3

The pipe to head removes the listing of . as the largest directory.

tail -n 0 -f /var/log/messages
2009-03-02 14:21:18
User: atoponce
Functions: tail
3

In this case, I'm keeping an eye on /var/log/messages, but of course any file will do. When I'm following a file, I generally don't want to see anything other than what has been added due to the command or service I've executed. This keeps everything clean and tidy for troubleshooting.

tail -f file1 (file2 .. fileN)
2009-03-02 11:13:42
User: hberth
Functions: tail
Tags: bash Ubuntu
3

Useful to e.g. keep an eye on several logfiles.

tail -n 15 /var/log/yum.log | tac
2009-03-02 08:56:04
User: alcik
Functions: tail
Tags: yum tail
0

It displays, last 15 yum operations (in last operation as first row order) with its dates. Change 15 to any number of operations you need to display or remove "| tac" to see it in reverse order (last operation as last row)

tail -1000 /some/file | vim -
2009-02-25 11:43:27
User: root
Functions: tail vim
17

The hyphen tells vim to open from STDOUT - saves having to create temporary files.

tail -n 20 ~/Library/Logs/FileSyncAgent.log
2009-02-19 05:05:21
User: sacrilicious
Functions: tail
-3

tail would be considered dull, but pair this with being able to push out unix commands over ARD, and life gets easier. (Same can be said for my TimeMachine scrape command, http://xrl.us/begrzb)