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Commands using tail from sorted by
Terminal - Commands using tail - 231 results
tail -f file | egrep --color=always $\|PATTERN
2009-10-15 13:08:30
User: sitaram
Functions: egrep file tail
Tags: color
-2

but you can't see the colors in that sample output :(

tail -f FILE | grep --color=always KEYWORD
dpkg --get-selections | cut -f1 | while read pkg; do dpkg -L $pkg | xargs -I'{}' bash -c 'if [ ! -d "{}" ]; then echo "{}"; fi' | tr '\n' '\000' | du -c --files0-from - | tail -1 | sed "s/total/$pkg/"; done
2009-10-12 14:57:54
User: pykler
Functions: bash cut du echo read sed tail tr xargs
Tags: Debian wajig
4

Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the

| sort -rn

which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side

Also you may need to run this as root as some files can only be checked by du if you can read them ;)

wget -q -O - 'http://wap.weather.gov.hk/' | sed -r 's/<[^>]+>//g;/^UV/q' | tail -n4
2009-09-25 02:36:46
User: dakunesu
Functions: sed tail wget
-1

"get Hong Kong weather infomation from HK Observatory

From Hong Kong Observatory wap site ;)"

other one showed alot of blank lines for me

find -type f -name "*.avi" -print0 | xargs -0 mplayer -vo dummy -ao dummy -identify 2>/dev/null | perl -nle '/ID_LENGTH=([0-9\.]+)/ && ($t +=$1) && printf "%02d:%02d:%02d\n",$t/3600,$t/60%60,$t%60' | tail -n 1
2009-09-24 15:50:39
User: syssyphus
Functions: find perl printf tail xargs
8

change the *.avi to whatever you want to match, you can remove it altogether if you want to check all files.

lsof -P -i -n | cut -f 1 -d " "| uniq | tail -n +2
ls -t | tail +6 | xargs rm
file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i x86_64 |nl | tail -1 | cut -f1 -f3; file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i "mach-o object i386" |nl | tail -1 | cut -f1 -f3
2009-09-11 16:43:27
Functions: cut file grep nl tail
-2

Not as far off as you thought, now is it?

-mac fanboy

find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'
2009-09-08 08:25:45
User: karpoke
Functions: awk find tail wc xargs
Tags: awk find wc
0

This is really fast :)

time find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'

204753

real 0m0.191s

user 0m0.068s

sys 0m0.116s

ls -lct /etc/ | tail -1 | awk '{print $6, $7, $8}'
2009-09-04 16:52:50
User: peshay
Functions: awk ls tail
5

shows also time if its the same year or shows year if installed before actual year and also works if /etc is a link (mac os)

file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -i x86_64 |nl |tail -1 |cut -f1 -f3 && file /System/Library/Extensions/*.kext/Contents/MacOS/* |grep -v x86_64 |nl |tail -1 |cut -f1 -f3
2009-09-03 14:28:02
Functions: cut file grep nl tail
-1

Next time you see a mac fanboy bragging about 64-bitness of 10.6 give him this so he might sh?

ls -lct /etc | tail -1 | awk '{print $6, $7}'
2009-09-03 10:26:37
User: MrMerry
Functions: awk ls tail
10

Show time and date when you installed your OS.

sudo find /var/log/ -mtime -7 -type f | xargs du -ch | tail -n1
2009-08-27 14:18:47
User: alvinx
Functions: du find sudo tail xargs
2

get diskusage of files (in this case logfiles in /var/log) modified during the last n days:

sudo find /var/log/ -mtime -n -type f | xargs du -ch

n -> last modified n*24 hours ago

Numeric arguments can be specified as

+n for greater than n,

-n for less than n,

n for exactly n.

=> so 7*24 hours (about 7 days) is -7

sudo find /var/log/ -mtime -7 -type f | xargs du -ch | tail -n1
mirror=ftp://somemirror.com/with/alot/versions/but/no/latest/link; latest=$(curl -l $mirror/ 2>/dev/null | grep util | tail -1); wget $mirror/$latest
2009-08-24 15:58:31
User: peshay
Functions: grep tail wget
4

to download latest version of "util", maybe insert a sort if they wont be shown in right order.

curl lists all files on mirror, grep your util, tail -1 will gets the one lists on the bottom and get it with wget

find dir/ -type f | xargs tail -fqn0
2009-08-21 18:05:12
User: chickenzilla
Functions: find tail xargs
1

The `-q' arg forces tail to not output the name of the current file

mysql -u<user> -p<password> -s -e 'DESCRIBE <table>' <database> | tail -n +1 | awk '{ printf($1",")}' | head -c -1
nslookup commandlinefu.com|sed 's/[^0-9. ]//g'|tail -n 1|awk -F " " '{print $2}'
2009-08-07 17:32:55
User: thundernode
Functions: awk nslookup sed tail
1

I use this in a script on my openwrt router to check if my DynDNS needs to be updated, saves your account from being banned for blank updates.

ps -o rss -C httpd | tail -n +2 | (sed 's/^/x+=/'; echo x) | bc
2009-07-31 15:15:08
Functions: echo ps sed tail
4

Display the amount of memory used by all the httpd processes. Great in case you are being Slashdoted!

echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | head -n5 | tail -1 | cut -f2 -d-
ls -t1 | head -n1 | xargs tail -f
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.