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Commands using printf from sorted by
Terminal - Commands using printf - 154 results
export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | toilet -f shadow'
2009-10-23 07:56:30
User: m33600
Functions: date echo export printf watch
0

already described on the other two versions, this one uses ascii characters on game style to display elapsed time.

export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | osd_cat -o 20 -d 1 -p bottom'
2009-10-23 07:47:11
User: m33600
Functions: date echo export printf watch
0

Variation of the theme, this one blinks in low profile on top level of X, ie, it is visible, indeed small.

Try changing fonts and sizes of osd_cat

export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds)'
2009-10-23 07:31:44
User: m33600
Functions: date echo export printf watch
3

Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch

Shows elapsed time from start of script in hh:mm:ss format

Non afected by system slow down due to the use of date.

ord() { printf "%d\n" "'$1"; }
2009-10-17 22:02:52
User: zude
Functions: printf
1

printf treats first char after single ' as numeric equivalent

printf "%d\n" "'A" "'B"
chr() { printf \\$(printf %o $1); }
chr () { printf \\$(($1/64*100+$1%64/8*10+$1%8)); }
2009-10-15 07:01:54
User: dennisw
Functions: printf
5

I've corrected the function. My octal conversion formula was completely wrong. Thanks to pgas at http://mywiki.wooledge.org/BashFAQ/071 for setting me straight. The new function is from pgas and is very fast.

(printf "PERMISSIONS LINKS OWNER GROUP SIZE MONTH DAY HH:MM PROG-NAME\n" \ ; ls -l | sed 1d) | column -t
cat file.txt | while read line; do printf "%7.2f -> %7.2f\n" $line; done
find -type f -name "*.avi" -print0 | xargs -0 mplayer -vo dummy -ao dummy -identify 2>/dev/null | perl -nle '/ID_LENGTH=([0-9\.]+)/ && ($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.

printf "%02u " {3..20}; echo
2009-09-18 18:48:41
User: Escher
Functions: printf
Tags: bash strings
0

emulates bash4's "echo {03..20}"

Uses bash3 builtin function printf

yes "$(seq 1 255)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
printf '%*s\n' 20 | tr ' ' '#'
printf "%'d\n" 1234567
2009-08-15 14:48:56
User: twfcc
Functions: printf
3

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})
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
4

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
0

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 $tokill;
yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
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
11

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

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

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
3

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
Functions: awk printf sudo zcat
22

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"
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
0

works the same as R's t()