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Commands using tail from sorted by
Terminal - Commands using tail - 222 results
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.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
history | perl -lane '$lsize{$_} = scalar(@F); if($longest<$lsize{$_}) { $longest = $lsize{$_}; print "$_"; };' | tail -n1
2009-03-19 02:52:30
User: salparadise
Functions: perl tail
Tags: history perl
3
Up
Down
find the longest command in your history
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
INFILE=/path/to/your/backup.img; MOUNTPT=/mnt/foo; PARTITION=1; mount "$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
Down
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).

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
Down
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".

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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...

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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.

Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -f file1 (file2 .. fileN)
2009-03-02 11:13:42
User: hberth
Functions: tail
Tags: bash Ubuntu
3
Up
Down
Prints new content of files

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

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -n 15 /var/log/yum.log | tac
2009-03-02 08:56:04
User: alcik
Functions: tail
Tags: yum tail
0
Up
Down
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
17
Up
Down
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
Up
Down
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
Down
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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cat -n $file | tail -n 100 && head -n number-of-lines-you-want-to-keep > newfile
2009-02-15 01:02:10
User: bbelt16ag
Functions: cat head tail
-1
Up
Down
removing those pesky malformed lines at the end of a text file..

tells you the number of lines in said file, and then tail the last 100 lines ( or how many are messed up) then u take the total amount of lines and then subract the 100 or so lines u DONT WANT, then do a head -n $new_number and then redirect it to new file.db

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tail -f /var/log/messages
2009-02-12 19:30:33
User: nicdev
Functions: tail
-3
Up
Down
View new log messages in real time

Use this command to see logs update in real time

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head -1000 < lines.txt | tail -1
2009-02-08 06:41:20
User: wbx
Functions: head tail
-2
Up
Down
get line#1000 from text.
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
alias nsl 'netstat -f inet | grep -v CLOSE_WAIT | cut -c-6,21-94 | tail +2'
2009-02-07 18:54:12
User: mnikhil
Functions: alias cut grep tail
3
Up
Down
show all programs connected or listening on a network port

Use the aliased command 'nsl'

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view `ls -1 access_log.* | tail -n 1`
2009-02-06 18:38:25
User: jimjmarion
Functions: tail
0
Up
Down
View latest apache access log

This command opens the latest, most current rotating apache access log for visual analysis and inspection. Run this command from the apache log directory. For error logs, replace access_log with error_log.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tail -f <filename> | grep -C <# of lines to show above and below> <text>
2009-02-06 17:19:01
User: manalang
Functions: grep tail
4
Up
Down
Live filter a log file using grep and show x# of lines above and below
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
(> errors.log) && tail -f !^
2009-02-03 16:08:19
User: root
Functions: tail
2
Up
Down
Flush and then immediately start watching a file

This is useful for keeping an eye on an error log while developing. The !^ pulls the first arg from the previous command (which needs to be run in a sub-shell for this shortcut to work).

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tail -10000 access_log | awk '{print $1}' | sort | uniq -c | sort -n | tail
2009-01-25 21:01:52
User: root
Functions: awk sort tail uniq
20
Up
Down
Analyse an Apache access log for the most common IP addresses

This uses awk to grab the IP address from each request and then sorts and summarises the top 10.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate