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Commands using tail

Commands using tail from sorted by
Terminal - Commands using tail - 208 results
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]) }'
2009-10-29 12:49:01
User: georgz
Functions: awk ps tail
7
Up
Down
cpu and memory usage top 10 under Linux

The original version gives an error, here is the correct output

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tail -F file | egrep --color 'pattern|$'
2009-10-16 04:01:14
User: sklm
Functions: egrep file tail
Tags: color
6
Up
Down
tail, with specific pattern colored
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tail -f file | egrep --color=always $\|PATTERN
2009-10-15 13:08:30
User: sitaram
Functions: egrep file tail
Tags: color
-2
Up
Down
tail, with specific pattern colored

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

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tail -f FILE | grep --color=always KEYWORD
2009-10-15 06:54:45
User: dennisw
Functions: grep tail
Tags: color
0
Up
Down
colored tail
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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
5
Up
Down
List your largest installed packages.

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 ;)

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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
Up
Down
get Hong Kong weather infomation from HK Observatory

"get Hong Kong weather infomation from HK Observatory

From Hong Kong Observatory wap site ;)"

other one showed alot of blank lines for me

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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
Tags: video audio mplayer perl find
8
Up
Down
Get the total length of all video / audio in the current dir (and below) in H:m:s

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

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lsof -P -i -n | cut -f 1 -d " "| uniq | tail -n +2
2009-09-19 21:23:54
User: edo
Functions: cut tail uniq
Tags: bash grep lsof internet
28
Up
Down
Show apps that use internet connection at the moment.

show only the name of the apps that are using internet

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ls -t | tail +6 | xargs rm
2009-09-16 06:33:07
User: negyvenot
Functions: ls tail xargs
Tags: ls
2
Up
Down
Delete all but the latest 5 files

yes 6 (tail from 6th line)

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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
User: digitalshadow
Functions: cut file grep nl tail
-2
Up
Down
How far is Mac OS X 10.6 from 64-bit?

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

-mac fanboy

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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
Up
Down
Make a statistic about the lines of code

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

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ls -lct /etc/ | tail -1 | awk '{print $6, $7, $8}'
2009-09-04 16:52:50
User: peshay
Functions: awk ls tail
4
Up
Down
When was your OS installed?

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)

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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
User: commandlinefu
Functions: cut file grep nl tail
-1
Up
Down
How far is Mac OS X 10.6 from 64-bit?

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

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ls -lct /etc | tail -1 | awk '{print $6, $7}'
2009-09-03 10:26:37
User: MrMerry
Functions: awk ls tail
9
Up
Down
When was your OS installed?

Show time and date when you installed your OS.

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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
Up
Down
get diskusage of files modified during the last n days

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
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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
Up
Down
get the latest version

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

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find dir/ -type f | xargs tail -fqn0
2009-08-21 18:05:12
User: chickenzilla
Functions: find tail xargs
1
Up
Down
follow the content of all files in a directory

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

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mysql -u<user> -p<password> -s -e 'DESCRIBE <table>' <database> | tail -n +1 | awk '{ printf($1",")}' | head -c -1
2009-08-17 12:54:44
User: Cowboy
Functions: awk head tail
2
Up
Down
Get table column names from an MySQL-database in comma-seperated form
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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
Up
Down
Get the ip registered to a domain on OpenWRT

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.

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ps -o rss -C httpd | tail -n +2 | (sed 's/^/x+=/'; echo x) | bc
2009-07-31 15:15:08
User: ricardoarguello
Functions: echo ps sed tail
4
Up
Down
How much RAM is Apache using?

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

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echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | head -n5 | tail -1 | cut -f2 -d-
2009-07-31 06:49:52
User: beerbrain
Functions: cut echo head tail
Tags: sed tail futurama cut nc
-4
Up
Down
Get Futurama quotations from slashdot.org servers
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ls -t1 | head -n1 | xargs tail -f
2009-07-29 13:46:29
User: patko
Functions: head ls tail xargs
Tags: tail logs
0
Up
Down
Tail the most recently modified file
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head -$(($RANDOM % $(wc -l < file.txt) +1 )) file.txt | tail -1
2009-07-23 12:00:49
User: sharfah
Functions: head tail wc
-4
Up
Down
Pick a random line from a file

prints a random line

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tail -F file
2009-07-23 07:37:11
User: recursiverse
Functions: tail
Tags: tail logs
14
Up
Down
Follow tail by name (fix for rolling logs with tail -f)

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.

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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
Up
Down
Follow the most recently updated log files

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}

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