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Commands using tail

Commands using tail from sorted by
Terminal - Commands using tail - 211 results
tail -f /var/log/logfile|perl -e 'while (<>) {$l++;if (time > $e) {$e=time;print "$l\n";$l=0}}'
2011-06-21 10:28:26
User: madsen
Functions: perl tail time
Tags: perl tail
2
Up
Down
Realtime lines per second in a log file

Using tail to follow and standard perl to count and print the lps when lines are written to the logfile.

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head -n1 sample.txt | tail -n1
2011-06-14 17:45:04
User: gtcom
Functions: head tail
Tags: tail HEAD
-1
Up
Down
Extract specific lines from a text file using Stream Editor (sed)

You can actually do the same thing with a combination of head and tail. For example, in a file of four lines, if you just want the middle two lines:

head -n3 sample.txt | tail -n2

Line 1 --\

Line 2 } These three lines are selected by head -n3,

Line 3 --/ this feeds the following filtered list to tail:

Line 4

Line 1

Line 2 \___ These two lines are filtered by tail -n2,

Line 3 / This results in:

Line 2

Line 3

being printed to screen (or wherever you redirect it).

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history | tail -(n+1) | head -(n) | sed 's/^[0-9 ]\{7\}//' >> ~/script.sh
2011-06-08 13:40:58
User: unixmonkey15842
Functions: head sed tail
Tags: history bash sed tail script
1
Up
Down
Create a bash script from last n commands

Uses history to get the last n+1 commands (since this command will appear as the most recent), then strips out the line number and this command using sed, and appends the commands to a file.

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tail /var/log/auth.log -n 100
2011-05-29 21:00:58
User: authtoken
Functions: tail
-3
Up
Down
View last 100 lines of your SSH log
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ls -atr /home/reports/*.csv -o --time-sty=+%s | tail -1 | awk '{print systime()-$5}'
2011-05-12 13:58:56
User: MiKatp
Functions: awk ls tail
Tags: bash awk
0
Up
Down
Show seconds since modified of newest modified file in directory
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FILE=`ls -ltr /var/lib/pgsql/backups/daily/ | tail -n1 | awk '{print $NF}'`; TIME=`stat -c %Y /var/lib/pgsql/backups/daily/$FILE`; NOW=`date +%s`; echo $((NOW-TIME))
2011-05-12 13:21:37
User: allrightname
Functions: awk echo tail
Tags: bash awk stat mtime
0
Up
Down
Show seconds since modified of newest modified file in directory
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find . -printf '%d\n' | sort -n | tail -1
2011-04-25 18:38:12
User: dustindorroh
Functions: find sort tail
2
Up
Down
Find directory depth

Returns a the directory depth.

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find /var/log -iregex '.*[^\.][^0-9]+$' -not -iregex '.*gz$' 2> /dev/null | xargs tail -n0 -f | ccze -A
2011-04-17 18:09:25
User: brejktru
Functions: find tail xargs
Tags: unix ccze
0
Up
Down
View all new log messages in real time with color
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tail -f /var/log/messages | espeak
2011-04-08 10:24:49
User: dmytrish
Functions: tail
1
Up
Down
make computer speaking to you :)

you can listen to your computer, but don't be carried away

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tail -f somefile |tee >(grep --line-buffered '1' > one.txt) |tee >(grep --line-buffered '2' > two.txt)
2011-04-03 10:05:28
User: binaryten
Functions: grep tail tee
Tags: tee, grep, buffer, multiple, parallel, pipes
4
Up
Down
monitor a tail -f command with multiple processes

when using named pipes only one reader is given the output by default. Also, most commands piped to by grep use a buffer which save output until tail -f finishes, which is not convenient. Here, using a combination of tee, sub-processes and the --line-buffered switch in grep we can workaround the problem.

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history | awk '{print $2}' | awk 'BEGIN {FS="|"}{print $1}' | sort | uniq -c | sort -n | tail | sort -nr
2011-03-12 05:58:21
User: secretgspot
Functions: awk sort tail uniq
Tags: histogram
3
Up
Down
Display top Keywords from history
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curl http://www.discogs.com/search?q=724349691704 2> /dev/null | grep \/release\/ | head -2 | tail -1 | sed -e 's/^<div>.*>\(.*\)<\/a><\/div>/\1/'
2011-01-30 23:45:50
User: mrman
Functions: grep head sed tail
Tags: sed grep curl discogs UPC
0
Up
Down
Find artist and title of a music cd, UPC code given (first result only)

Changed wget to curl and it doesn't create a file anymore.

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wget http://www.discogs.com/search?q=724349691704 -O foobar &> /dev/null ; grep \/release\/ foobar | head -2 | tail -1 | sed -e 's/^<div>.*>\(.*\)<\/a><\/div>/\1/' ; rm foobar
2011-01-30 23:34:54
User: TetsuyO
Functions: grep head rm sed tail wget
Tags: sed wget grep discogs UPC
-1
Up
Down
Find artist and title of a music cd, UPC code given (first result only)

Substitute that 724349691704 with an UPC of a CD you have at hand, and (hopefully) this oneliner should return the $Artist - $Title, querying discogs.com.

Yes, I know, all that head/tail/grep crap can be improved with a single sed command, feel free to send "patches" :D

Enjoy!

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curl -s http://www.last.fm/user/$LASTFMUSER | grep -A 1 subjectCell | sed -e 's#<[^>]*>##g' | head -n2 | tail -n1 | sed 's/^[[:space:]]*//g'
2011-01-24 08:16:48
User: sn0opy
Functions: grep head sed tail
Tags: sed tail grep HEAD last.fm
-1
Up
Down
Fetch current song from last.fm
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/usr/bin/lynx -dump http://www.netins.net/dialup/tools/my_ip.shtml | grep -A2 "Your current IP Address is:" | tail -n1 | tr -d ' '|sed '/^$/d'| sed 's/^ *//g'
2010-12-20 15:29:53
User: juanmi
Functions: grep sed tail tr
-11
Up
Down
get you public ip address
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ping -q -c 1 www.google.com|tail -1|cut -d/ -f5
2010-12-15 10:36:17
User: LrdShaper
Functions: cut ping tail
1
Up
Down
Do one ping to a URL, I use this in a MRTG gauge graph to monitor connectivity
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alias -g R=' &; jobs | tail -1 | read A0 A1 A2 cmd; echo "running $cmd"; fg "$cmd"; zenity --info --text "$cmd done"; unset A0 A1 A2 cmd'
2010-12-13 17:44:36
User: pipeliner
Functions: alias echo fg jobs read tail unset
Tags: alias zsh zenity suffix jobs
1
Up
Down
zsh suffix to inform you about long command ending

make, find and a lot of other programs can take a lot of time. And can do not. Supppose you write a long, complicated command and wonder if it will be done in 3 seconds or 20 minutes. Just add "R" (without quotes) suffix to it and you can do other things: zsh will inform you when you can see the results.

You can replace zenity with other X Window dialogs program.

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du . -mak|sort -n|tail -10
2010-12-03 19:28:55
User: georgesdev
Functions: du sort tail
0
Up
Down
List 10 largest directories in current directory

du -m option to not go across mounts (you usually want to run that command to find what to destroy in that partition)

-a option to also list . files

-k to display in kilobytes

sort -n to sort in numerical order, biggest files last

tail -10 to only display biggest 10

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ls -1t --group-directories-first /path/to/dir/ | tail -n 1
2010-12-02 12:25:16
User: fpunktk
Functions: ls tail
1
Up
Down
get the oldest file in a directory

reverse the sorting of ls to get the newest file:

ls -1tr --group-directories-first /path/to/dir/ | tail -n 1

Problems:

If there are no files in the directory you will get a directory or nothing.

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tail -f /var/www/logs/domain.com.log | grep "POST /scripts/blog-post.php" | grep -v 192.168. | awk '{print $1}' | xargs -I{} iptables -I DDOS -s {} -j DROP
2010-11-30 06:22:18
User: tehusr
Functions: awk grep iptables tail xargs
1
Up
Down
Anti DDOS

Takes IP from web logs and pipes to iptables, use grep to white list IPs.. use if a particular file is getting requested by many different addresses.

Sure, its already down pipe and you bandwidth may suffer but that isnt the concern. This one liner saved me from all the traffic hitting the server a second time, reconfigure your system so your system will work like blog-post-1.php or the similar so legitimate users can continue working while the botnet kills itself.

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tail -f file |xargs -IX printf "$(date -u)\t%s\n" X
2010-11-25 11:23:13
User: unefunge
Functions: file printf tail xargs
Tags: tail xargs date printf logging
2
Up
Down
Monitor a file with tail with timestamps added
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tail -f file | awk '{now=strftime("%F %T%z\t");sub(/^/, now);print}'
2010-11-25 04:11:52
User: arcege
Functions: awk file tail
Tags: awk tail
7
Up
Down
Monitor a file with tail with timestamps added
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tail -f file | while read line; do printf "$(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
3
Up
Down
Monitor a file with tail with timestamps added

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

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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
5
Up
Down
Monitor a file with tail with timestamps added

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.

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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
0
Up
Down
Ranking of the most frequently used commands

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')

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