Commands using printf | commandlinefu.com

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Terminal - Commands using printf - 143 results

yes "$(seq 1 255)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done

2009-09-05 04:01:23

User: unixmonkey4581

Functions: printf read sleep yes

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cycle through a 256 colour palette

Rainbow, instead of greys

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printf '%*s\n' 20 | tr ' ' '#'

2009-08-15 22:38:01

User: twfcc

Functions: printf tr

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Emulate perl 'print "#" x 20, "\n"'

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printf "%'d\n" 1234567

2009-08-15 14:48:56

User: twfcc

Functions: printf

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formatting number with comma

it is not work with Cygwin's bash3.X. Test in Linux.

use printf "%'f" number while it is floating point number

mkdir $(printf '%03d\n' {1..100})

2009-08-14 11:35:43

User: twfcc

Functions: mkdir printf

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make 100 directories with leading zero, 001...100, using bash3.X

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printf '\!:1\0\!:1\0\!:2' | mmencode | tr -d '\n' | sed 's/^/AUTH PLAIN /'

2009-08-04 05:04:50

User: vwal

Functions: printf sed tr

Tags: smtp testing development

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Create AUTH PLAIN string to test SMTP AUTH session

I use this as an alias:

alias authplain "printf '\!:1\0\!:1\0\!:2' | mmencode | tr -d '\n' | sed 's/^/AUTH PLAIN /'"

then..

# authplain someuser@somedomain.com secretpassword

AUTH PLAIN c29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac2VjcmV0cGFzc3dvcmQ=

cat /dev/urandom|awk 'BEGIN{"tput cuu1" | getline CursorUp; "tput clear" | getline Clear; printf Clear}{num+=1;printf CursorUp; print num}'

2009-07-13 07:30:51

User: axelabs

Functions: awk cat printf

Tags: nawk awk clear tput

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Watch number of lines being processed on a clear screen

awk can clear the screen while displaying output. This is a handy way of seeing how many lines a tail -f has hit or see how many files find has found. On solaris, you may have to use 'nawk' and your machine needs 'tput'

tokill=`ps -fea|grep process|awk '{ printf $2" "}'`; kill -9 $tokill;

2009-07-11 01:40:29

User: jhansen

Functions: awk grep kill printf

-3

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kill some process (same as others) but parsing to a variable

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yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done

2009-07-03 13:58:02

User: frans0023

Functions: printf read sleep yes

Tags: color shell demo

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Print a great grey scale demo !

Seen here: http://www.pixelbeat.org/docs/terminal_colours/

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awk '/sshd/ && /Failed/ {gsub(/invalid user/,""); printf "%-12s %-16s %s-%s-%s\n", $9, $11, $1, $2, $3}' /var/log/auth.log

2009-04-16 00:56:23

User: frailotis

Functions: awk printf

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Displays the attempted user name, ip address, and time of SSH failed logins on Debian machines

A variation of a script I found on this site and then slimmed down to just use awk. It displays all users who have attempted to login to the box and failed using SSH. Pipe it to the sort command to see which usernames have the most failed logins.

i=10;for o in *.mp3; do i=$(printf "%02d" $i); mv $o $i$o; ((i = $i + 2)); done

2009-04-13 12:33:52

User: bazzawill

Functions: mv printf

-1

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Precide a bunch of files with a number in a pattern for example to indisperse a podcast backlock with more recent podcasts

This command adds the numbers 10, 12, 14 to a bunch of mp3's in the current working directory. You can then run the command replacing the inital i=10 with i=11 to add 11,13,15 in another directory then mv the files together and the first files interweave with the second group of files. I used this to weave a backlog of a podcast with other podcast so I didn't get sick of one while I was catching up. I started at 10 because printf blows up with 0 padded numbers 08 and 09 which kind of makes the printf command redundant as it was used to pad numbers 1 - 9 so they would come first and not get sorted incorrectly

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seq 6 | awk '{for(x=1; x<=5; x++) {printf ("%f ", rand())}; printf ("\n")}'

2009-03-24 21:33:38

User: kaan

Functions: awk printf seq

Tags: awk seq

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Display rows and columns of random numbers with awk

Displays six rows and five columns of random numbers between 0 and 1. If you need only one column, you can dispense with the "for" loop.

sudo zcat /var/log/auth.log.*.gz | awk '/Failed password/&&!/for invalid user/{a[$9]++}/Failed password for invalid user/{a["*" $11]++}END{for (i in a) printf "%6s\t%s\n", a[i], i|"sort -n"}'

2009-03-21 06:41:59

User: point_to_null

Functions: awk printf sudo zcat

Tags: Security awk brute force

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Brute force discover

Show the number of failed tries of login per account. If the user does not exist it is marked with *.

echo '123/7' |bc -l |xargs printf "%.3f\n"

2009-03-18 14:20:32

User: mrttlemonde

Functions: bc echo printf xargs

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Doing some floating point calculations with rounding (e.g. at the 3rd decimal)

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awk '{ for (f = 1; f <= NF; f++) a[NR, f] = $f } NF > nf { nf = NF } END { for (f = 1; f <= nf; f++) for (r = 1; r <= NR; r++) printf a[r, f] (r==NR ? RS : FS) }'

2009-03-10 05:35:22

User: MSBF

Functions: awk printf

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transpose a file

works the same as R's t()

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time vmware-cmd -l | while read x; do printf "$x"; vmware-cmd "$x" removesnapshots; done

2009-02-26 18:51:29

User: jcgam69

Functions: printf read time

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remove all snapshots from all virtual machines in vmware esx

Old snapshots can cause problems. It's best to remove them when finished. I use this script to remove all snapshots. The "while read" command is necessary because my vm names contain spaces. The "time" command reports how long the process runs.

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printf %d 0x`dd if=/dev/urandom bs=1 count=4 2>/dev/null | od -x | awk 'NR==1 {print $2$3}'`

2009-02-18 16:23:09

User: introp

Functions: awk od printf

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Big (four-byte) $RANDOM

Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

FAIL2BAN=`ps ax | grep fail2ban | grep -v grep | awk {'print $1'}` && if [ -n "$FAIL2BAN" ]; then printf "\n[INFO] Fail2Ban is running and the PID is %s\n\n" $FAIL2BAN; else printf "\n [INFO] Fail2Ban is not running\n\n"; fi

2009-02-11 04:36:49

User: fmdlc

Functions: awk grep printf

-6

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Check if Fail2Ban is Running

Check if Fail2Ban is running on the system and alert it with a message in the terminal

yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done

2009-02-05 12:01:37

User: pixelbeat

Functions: printf read sleep yes

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cycle through a 256 colour palette

just for fun

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