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Terminal - Commands using head - 216 results

TOTAL_RAM=`free | head -n 2 | tail -n 1 | awk '{ print $2 }'`; PROC_RSS=`ps axo rss,comm | grep [h]ttpd | awk '{ TOTAL += $1 } END { print TOTAL }'`; PROC_PCT=`echo "scale=4; ( $PROC_RSS/$TOTAL_RAM ) * 100" | bc`; echo "RAM Used by HTTP: $PROC_PCT%"

2010-02-26 20:29:45

User: d34dh0r53

Functions: awk echo grep head tail

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Print Memory Utilization Percentage For a specific process and it's children

Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

newest () { DIR=${1:-'.'}; CANDIDATE=`find $DIR -type f|head -n1`; while [[ ! -z $CANDIDATE ]]; do BEST=$CANDIDATE; CANDIDATE=`find $DIR -newer "$BEST" -type f|head -n1`; done; echo "$BEST"; }

2010-02-04 12:40:44

User: shadycraig

Functions: echo head

Tags: bash find files recursive

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A function to find the newest file in a directory

Works recusivley in the specified dir or '.' if none given.

Repeatedly calls 'find' to find a newer file, when no newer files exist you have the newest.

In this case 'newest' means most recently modified. To find the most recently created change -newer to -cnewer.

du -s * | sort -nr | head | cut -f2 | parallel -k du -sh

2010-01-28 12:59:14

User: unixmonkey8046

Functions: cut du head sort

Tags: du xargs parallel

-2

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List top ten files/directories sorted by size

If a directory name contains space xargs will do the wrong thing. Parallel https://savannah.nongnu.org/projects/parallel/ deals better with that.

2010-01-21 19:52:28

User: connorsy

Functions: cut head paste sed sort tr

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Create unique email addresses directly from the US census site*Full command in comments

** Replace the ... in URLS with:

www.census.gov/genealogy/www/data/1990surnames

Couldn't fit in 256

Created on Ubuntu 9.10 but nothing out of the ordinary, should work anywhere with a little tweaking. 5163 is the number of unique first names you get when combine the male and female first name files from. http://www.census.gov/genealogy/www/data/1990surnames/names_files.html

ifconfig | grep -B 1 "inet addr:" | head -1 | cut -d" " -f1

2010-01-04 23:02:57

User: jasonwalsh

Functions: cut grep head ifconfig

-2

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Get name of first configured interface

Get the line containing "inet addr:" and the line before that, get down to only the first line, and then get the first word on that line, which should be the interface.

tr -dc 'a-zA-Z0-9' < /dev/urandom | head -c10

2009-12-01 14:22:20

User: Phil

Functions: head tr

-1

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generate random password

A slightly shorter version. Also doesn't put a return character at the end of the password

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

This is sample output - yours may be different.

$ cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

  60 .+-----+------+------+------+-------+------+------+------+------+-----++
     +      +      +      +      +       +      +      +      +      +      +
     |                                                                      |
  50 ++                                                                    ++
     |                                                                      |
     |.                                                                     |
     |.                                                                     |
  40 ++                                                                    ++
     |                                                                      |
     | ..                                                                   |
  30 ++                                                                    ++
     |   .                                                                  |
     |                                                                      |
  20 ++  ..                                                                ++
     |     ..                                                               |
     |       ..                                                             |
     |         ...                                                          |
  10 ++           ....                                                     ++
     |                ...............                                       |
     +      +      +      +      +   .......................................+
   0 ++-----+------+------+------+-------+------+------+------+------+-----++
     0      10     20     30     40      50     60     70     80     90    100

2009-11-20 14:53:26

User: taliver

Functions: awk cat head printf sort tr uniq

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Plot frequency distribution of words from files on a terminal.

Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files.

mkpasswd() { head -c $(($1)) /dev/urandom | uuencode - | sed -n 's/.//;2s/$.\{'$1'\}$.*/\1/p' ;}

2009-11-19 14:27:52

User: taliver

Functions: head sed uuencode

-3

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Random password generating function

This uses urandom to produce a random password. The random values are uuencoded to ensure only printable characters. This only works for a number of characters between 1 and 60.

for i in *.avi; do echo -n "$i:";mediainfo $i|head | grep PlayTime | cut -d: -f2 ; done | sort -t: -k2 -r

2009-11-09 12:42:20

User: yooreck

Functions: cut echo grep head sort

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Sort movies by length, longest first

Similar but using mediainfo instead of totem-something

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ps -eo pcpu,user,pid,cmd | sort -r | head -5

2009-11-03 14:41:55

User: ferqwerty

Functions: head ps sort

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Display top 5 processes consuming CPU

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shuf -i 1-49 | head -n6 | sort -n| xargs

2009-10-22 12:54:08

User: ioggstream

Functions: head sort

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lotto generator

note the xargs at the end

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echo $(shuf -i 1-49 | head -n6 | sort -n)

2009-10-22 06:48:20

User: twfcc

Functions: echo head sort

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lotto generator

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for f in *.html; do head -n -1 $f > temp; cat temp > $f; rm temp; done

2009-10-12 12:49:18

User: Sunng

Functions: cat head rm

-1

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remove the last line of all html files in a directory

Some malicious program appends a iframe or script tag to you web pages on some server, use this command to clean them in batch.

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head -c10 <(echo $RANDOM$RANDOM$RANDOM)

2009-10-09 15:09:02

User: jgc

Functions: echo head

Tags: HEAD random

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Outputs a 10-digit random number

Makes use of $RANDOM environment variable.

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tr -c -d 0-9 < /dev/urandom | head -c 10

2009-10-09 11:58:30

User: hfs

Functions: head tr

Tags: HEAD tr urandom

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Outputs a 10-digit random number

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head -c4 /dev/urandom | od -N4 -tu4 | sed -ne '1s/.* //p'

2009-10-08 11:27:20

User: opexxx

Functions: head od sed

Tags: sed HEAD od

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Outputs a 10-digit random number

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find ~/Music -daystart -mtime -60 -name *mp3 -printf "%T@\t%p\n" | sort -f -r | head -n 30 | cut -f 2

2009-10-06 17:57:04

User: iadbungler

Functions: cut find head sort

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Print a list of the 30 last modified mp3s sorted by last first

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awk '{print $1}' /var/log/httpd/access_log | sort | uniq -c | sort -rnk1 | head -n 10

2009-08-30 15:32:26

User: flip387

Functions: awk head sort uniq

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Top 10 requestors by IP address from Apache/NCSA Logs

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for x in `seq 0 25 $(curl "http://www.commandlinefu.com/commands/browse"|grep "Terminal - All commands" |perl -pe 's/.+(\d+),(\d+).+/$1$2/'|head -n1)`; do curl "http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/$x" ; done > a.txt

2009-08-27 11:02:53

User: SuperFly

Functions: grep head perl

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Download entire commandlinefu archive to single file

'jot' does not come with most *nix distros, so we need to use seq to make it work. This version tested good on Fedora 11.

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for x in `jot - 0 \`curl "http://www.commandlinefu.com/commands/browse"|grep "Terminal - All commands" |perl -pe 's/.+(\d+),(\d+).+/$1$2/'|head -n1\` 25`; do curl "http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/$x" ; done >a.txt

2009-08-25 21:57:15

User: stinkerweed999

Functions: grep head perl

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Download entire commandlinefu archive to single file

This is an extension of a previous command by satyavvd on 2009-07-23 12:04:02, but this one grabs the whole archive. Hard coded numbers in previous script capped number of commands that could be fetched. This one grabs them all regardless of how big the archive gets.

find / -type f -exec wc -c {} \; | sort -nr | head -100

2009-08-22 09:38:44

User: hemanth

Functions: find head sort wc

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List files and sizes

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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

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Get table column names from an MySQL-database in comma-seperated form

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randpw(){ < /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-16};echo;}

2009-08-07 07:30:57

User: frozenfire

Functions: head tr

Tags: password random

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Generate random password

Generates password consisting of alphanumeric characters, defaults to 16 characters unless argument given.

seq 1 12 | sed 1,5d ; seq 1 12 | head --lines=-5

2009-08-01 00:41:52

User: flux

Functions: head sed seq

Tags: sed tail HEAD fun

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skipping five lines, at top, then at bottom

Strangely enough, there is no option --lines=[negative] with tail, like the head's one, so we have to use sed, which is very short and clear, you see.

Strangely more enough, skipping lines at the bottom with sed is not short nor clear. From Sed one liner :

# delete the last 10 lines of a file

$ sed -e :a -e '$d;N;2,10ba' -e 'P;D' # method 1

$ sed -n -e :a -e '1,10!{P;N;D;};N;ba' # method 2

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

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Get Futurama quotations from slashdot.org servers

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