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Commands using tail

Commands using tail from sorted by
Terminal - Commands using tail - 208 results
cp `ls -x1tr *.jpg | tail -n 1` newest.jpg
2009-06-17 20:32:04
User: Psychodad
Functions: cp tail
Tags: tail ls newest file webcam
1
Up
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get newest jpg picture in a folder

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.

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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
5
Up
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Monitor logs in Linux using Tail

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.

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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
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coloured tail

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

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

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lynx -source http://www.commandlinefu.com/commands/random | sed 's/<[^>]*>//g' | head -1037 | tail -10 | sed -e 's/^[ \t]*//' | sed '/^$/d' | head -2
2009-06-02 09:48:59
User: lxtips
Functions: head sed tail
Tags: sed lynx
-2
Up
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print random commandlinefu.com submission

ok I'm sure it's not pretty

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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
Up
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List last opened tabs in firefox browser

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.

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tail -f --retry /var/log/syslog /var/log/auth.log | ccze -A
2009-05-13 00:02:50
User: Yury
Functions: tail
0
Up
Down
Syslog System Reporting in a shell
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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]) }'
2009-05-05 16:54:25
User: feraudet
Functions: awk ps tail
1
Up
Down
cpu and memory usage top 10 under Linux

It's like `prstat -t` under Solaris

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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
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Jump to a song in your XMMS2 playlist, based on song title/artist

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 !

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ps aux | sort +2n | tail -20
2009-03-31 12:03:34
User: dopeman
Functions: ps sort tail
3
Up
Down
Show the 20 most CPU/Memory hungry processes

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
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du -xk | sort -n | tail -20
2009-03-30 11:37:43
User: dopeman
Functions: du sort tail
7
Up
Down
Find the 20 biggest directories on the current filesystem

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.

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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
Tags: vmstat monitoring
3
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Output system statistics every 5 seconds with timestamp

See man vmstat for information about the statistics.

This does the same thing without the timestamp:

vmstat 5
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tail -f logfile.log | cut -b 1-80
2009-03-26 18:41:57
User: plasticboy
Functions: cut tail
Tags: tail log
3
Up
Down
Tail a log file with long lines truncated

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.

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history | perl -lane '$lsize{$_} = scalar(@F); if($longest<$lsize{$_}) { $longest = $lsize{$_}; print "$_"; };' | tail -n1
2009-03-19 02:52:30
User: salparadise
Functions: perl tail
Tags: history perl
3
Up
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find the longest command in your history
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INFILE=/path/to/your/backup.img; MOUNTPT=/mnt/foo; PARTITION=1; mount "$INFILE" "$MOUNTPT" -o loop,offset=$[ `/sbin/sfdisk -d "$INFILE" | grep "start=" | head -n $PARTITION | tail -n1 | sed 's/.*start=[ ]*//' | sed 's/,.*//'` * 512 ]
2009-03-06 21:29:13
User: Alanceil
Functions: grep head mount sed tail
Tags: backup Linux mount mount point sfdisk image partition recovery restore
6
Up
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Mount a partition from within a complete disk dump

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).

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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
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Quickly analyze apache logs for top 25 most common IP addresses.

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

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tail -f *[!.1][!.gz]
2009-03-06 16:24:44
User: piscue
Functions: tail
Tags: bash tail wildcard log
5
Up
Down
useful tail on /var/log to avoid old logs or/and gzipped files

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

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du | sort -n | tail -11 | head
2009-03-04 16:06:34
User: phage
Functions: du sort tail
-3
Up
Down
Get top 10 largest directories under cwd

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

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -n 0 -f /var/log/messages
2009-03-02 14:21:18
User: atoponce
Functions: tail
3
Up
Down
Watch contents of a file grow

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.

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tail -f file1 (file2 .. fileN)
2009-03-02 11:13:42
User: hberth
Functions: tail
Tags: bash Ubuntu
2
Up
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Prints new content of files

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

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tail -n 15 /var/log/yum.log | tac
2009-03-02 08:56:04
User: alcik
Functions: tail
Tags: yum tail
0
Up
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Check the last 15 package operations (on yum systems)

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)

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tail -1000 /some/file | vim -
2009-02-25 11:43:27
User: root
Functions: tail vim
Tags: Text Processing vim
16
Up
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Pipe STDOUT to vim

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

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tail -n 20 ~/Library/Logs/FileSyncAgent.log
2009-02-19 05:05:21
User: sacrilicious
Functions: tail
-3
Up
Down
Quick scrape of recent mobile home dir file sync for Mac Admins - tested with shell: bash, Mac OSX 10.5

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)

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syslog -F '$Time $Message' -k Sender /System/Library/CoreServices/backupd -k Time ge -72h | tail -n 30
2009-02-19 04:33:25
User: sacrilicious
Functions: tail
0
Up
Down
Show some details of recent Leopard Time Machine activity - shell: bash, Mac OSX 10.5

While they are few config options and even fewer useful details regarding what actually is being sent by the time machine 'backupd' process, this can at least tell you its doing something, how much it's doing, and exactly how often. Via macosxhints, http://xrl.us/begrwa, which in turn was via comments

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tail -f /path/to/timestamped/files/file-*(om[1])
2009-02-16 22:55:16
User: karld
Functions: tail
5
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Always tail/edit/grep the latest file in a directory of timestamped files

zsh only

If you have this command in your history, you can always re-run it and have it reference the latest file.

The glob matches all timestamped files and then the resulting array is sorted by modification time (m) and then the first element in the sorted array is chosen (the latest)

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netstat -pant 2> /dev/null | grep SYN_ | awk '{print $5;}' | cut -d: -f1 | sort | uniq -c | sort -n | tail -20
2009-02-16 08:49:38
User: unixmonkey982
Functions: awk cut grep netstat sort tail uniq
3
Up
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List top 20 IP from which TCP connection is in SYN_RECV state

List top 20 IP from which TCP connection is in SYN_RECV state.

Useful on web servers to detect a syn flood attack.

Replace SYN_ with ESTA to find established connections

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