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Commands using printf

Commands using printf from sorted by
Terminal - Commands using printf - 139 results
alias clearscrollback='clear;printf %b "\033[3J"'
2013-03-19 14:18:22
User: richardellisjr
Functions: alias printf
0
Up
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Create an alias command that clears the screen and scroll back buffer (in putty and xterm)
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count='1'; for i in *.jpg; do mv $i $(printf '%01d'.jpg $count); (( count++ )); done
2013-02-20 06:38:25
User: lalanza808
Functions: mv printf
-1
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Batch rename and number files

The '1' in '%01d' changes the amounts of digits in the integer, eg. 1 vs 0001.

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awk '{for (i=9;i<=NF;i++) {printf "%s",$i; printf "%s", " ";}; printf "\n"}'
2013-02-12 13:57:43
User: adimania
Functions: awk printf
Tags: awk
0
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Print data from field 9 till the end separated by a white space and new record separated by newline.

It'll print the file names preserving the spaces in their names and adding new line after every new filename.

I wrote this to quickly find out how many files in any directory is owned by a particular user. This can be extended using pipe and grep to do much more.

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find . -name '*.jpg' | awk 'BEGIN{ a=0 }{ printf "mv %s name%01d.jpg\n", $0, a++ }' | bash
2013-02-07 06:12:37
User: doublescythe
Functions: awk find printf
0
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Batch rename and number files

This command will take the files in a directory, rename them, and then number them from 1...N.

Black belt stuff.

Hell of a time saver.

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today() { printf '%(%Y-%m-%d)T\n' -1; } ## bash-4
2013-01-27 06:17:25
User: cfajohnson
Functions: printf
2
Up
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Print today's date in ISO format without calling an external command (bash 4)
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function up { cd $(eval printf '../'%.0s {1..$1}) && pwd; }
2013-01-21 12:57:45
User: michelsberg
Functions: cd eval printf
Tags: cd directory
5
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move up through directories faster (set in your /etc/profile or .bash_profile)

Usage:

up N

I did not like two things in the submitted commands and fixed it here:

1) If I do cd - afterwards, I want to go back to the directory I've been before

2) If I call up without argument, I expect to go up one level

It is sad, that I need eval (at least in bash), but I think it's safe here.

eval is required, because in bash brace expansion happens before variable substitution, see http://rosettacode.org/wiki/Repeat_a_string#Using_printf

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while(true); do printf "%s\f" $(date +%T); sleep 1; done | sm -
2013-01-14 17:13:34
User: claudius
Functions: date printf sleep
Tags: time clock sm
1
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Print the current time on the whole screen, updated every second

http://www.joachim-breitner.de/projects#screen-message now also supports reading stdin continuously to update what it shows, different ?slides? separated by a form feed character. Here, we feed the current time into it each second to create a large clock.

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for code in $(seq -w 0 255); do for attr in 0 1; do printf "%s-%03s %bTest%b\n" "${attr}" "${code}" "\e[${attr};38;05;${code}m" "\e[m"; done; done | column -c $((COLUMNS*2))
2013-01-13 18:23:44
User: claudius
Functions: column printf seq
Tags: bash color colors
0
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Show numerical values for each of the 256 colors in bash for bold and normal fonts

Shows the ?rendering? for each of the 256 colours in both the bold and normal variant. Using seq is helpful to get even lines, passing $((COLUMNS*2)) to column sort-of-handles the nonprintable characters.

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tshark -r *.eth -S -R "ajp13" -d tcp.port==9009,ajp13 -s 0 -l -V | awk '/Apache JServ/ {p=1} /^ *$/ {p=0;printf "\n"} (p){printf "%s\n", $0} /^(Frame|Internet Pro|Transmission Control)/ {print $0}'
2013-01-10 21:12:51
User: tsureshkumar
Functions: awk printf
Tags: tshark
0
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read ajp13 packet contents on terminal using tshark 1.4.15

if you have a capture file *.eth, and ajp protocol is in use on port 9009, you can paste the above command. You can change the fiile and port name

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du . | sort -nr | awk '{split("KB MB GB TB", arr); idx=1; while ( $1 > 1024 ) { $1/=1024; idx++} printf "%10.2f",$1; print " " arr[idx] "\t" $2}' | head -25
2012-12-03 02:59:13
User: agas
Functions: awk du head printf sort
0
Up
Down
List the size (in human readable form) of all sub folders from the current location

Lists the size in human readable form and lists the top 25 biggest directories/files

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while true; do printf "\e[32m%X\e[0m" $((RANDOM%2)); for ((i=0; i<$((RANDOM%128)); i++)) do printf " "; done; done
2012-11-27 10:40:42
User: sandre
Functions: printf
Tags: bash color random Matrix
0
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Matrix Style

Unlike other alternatives, this command only relies on bash builtins and should also work on windows platforms with the bash executable.

Sparseness corresponds to the number 128 and can be adjusted. To print all possible digits instead of only 0 and 1 replace RANDOM%2 by RANDOM%10 or RANDOM%16 to add letters [A-F].

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hl-nonprinting () { local C=$(printf '\033[0;36m') B=$(printf '\033[0;46m') R=$(printf '\033[0m') np=$(env printf "\u00A0\uFEFF"); sed -e "s/\t/${C}&#9657;&$R/g" -e "s/$/${C}&#8267;$R/" -e "s/[$np]/${B}& $R/g";}
2012-11-07 10:09:40
User: unhammer
Functions: env printf sed
Tags: tabs whitespace non-printing
-1
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bash function to highlight non-printing characters: tab, newline, BOM, nbsp

Can't see it here, but the non-breaking space is highlighted :)

Of course,

cat -t -e

achieves something similar, but less colourful.

Could add more code points from https://en.wikipedia.org/wiki/Space_%28punctuation%29#Spaces_in_Unicode

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hl-nonprinting () { local C=$(printf '\033[0;36m') R=$(printf '\033[0m'); sed -e "s/\t/${C}&#9657;&$R/g" -e "s/$/${C}&#8267;$R/";}
2012-11-07 09:55:48
User: unhammer
Functions: printf sed
Tags: tabs whitespace non-printing
-1
Up
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bash function to "highlight" tabs and linebreaks

I don't think it's possible to give a (background) colour to the tab itself, since a tab is, IIUC, simply a command to the terminal to move to the right. Nevertheless, this "highlighting" can be helpful when working with tab-separated files.

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for i in `ls /var/log/sa/|grep -E "sa[0-9][0-9]"`;do echo -ne "$i -- ";sar -r -f /var/log/sa/$i|awk '{ printf "%3.2f\n",($4-$6-$7)*100/(3+$4)}'|grep -Eiv "average|linux|^ --|0.00|^-" |awk '{sum+=$1 }END{printf "Average = %3.2f%%\n",sum/NR}';done
2012-10-25 17:00:58
User: omatictost
Functions: awk echo grep printf
0
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SAR - List the average memory usage for all days recorded under '/var/log/sa/*' using sar -r.
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/sbin/ifconfig |awk '/bond|eth/{getline i;printf $0" ";printf "%s\n", i" "}'|awk '{print $1,substr($7,6)}'
2012-10-25 16:08:15
User: omatictost
Functions: awk printf
0
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Aligns NIC device names and associated IPs.
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find -maxdepth 3 -type d | while read -r dir; do printf "%s:\t" "$dir"; find "$dir" | wc -l; done
2012-10-15 15:00:09
User: brainstorm
Functions: find printf read wc
1
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Count all files in directories recursively with find

Counts the files present in the different directories recursively. One only has to change maxdepth to have further insight in the directory hierarchy.

Found at unix.stackexchange.com:

http://unix.stackexchange.com/questions/4105/how-do-i-count-all-the-files-recursively-through-directories

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echo -e "\e[32m"; while :; do printf '%*c' $(($RANDOM % 30)) $(($RANDOM % 2)); done
2012-09-25 17:36:25
User: fernandomerces
Functions: echo printf
Tags: random Matrix
2
Up
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Binary digits Matrix effect

Prints 0's and 1's in The Matrix style. You can easily modify to print 0-9 digits using $RANDOM %10 insted of %2.

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grep -H voluntary_ctxt /proc/*/status |gawk '{ split($1,proc,"/"); if ( $2 > 10000000 ) { printf $2 " - Process : "; system("ps h -o cmd -p "proc[3]) } }' | sort -nk1,1 | sed 's/^/Context Switches: /g'
2012-09-01 19:43:47
User: jperkster
Functions: gawk grep printf sed sort
0
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Find highest context switches

This command will find the highest context switches on a server and give you the process listing.

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for ((i=65;i<91;i++)); do printf "\\$(printf '%03o' $i) "; done
2012-08-24 13:24:36
User: slappy
Functions: printf
Tags: shell increment alphanumeric
0
Up
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Alphanumeric incrementating (uppercase)

Could easily be used for lowercase --> ((i=97;i

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alarmclock() { [ $1 ] || echo Parameter TIME is missing. 1>&2 && return 1 ; ( sleep $1 ; for x in 9 8 7 6 5 4 3 2 1 ; do for y in `seq 0 $[ 10 - $x ] ` ; do printf "\a"; sleep 0.$x ; done ; done ) & }
2012-08-16 15:35:15
User: lkj
Functions: echo printf return sleep
0
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Alarmclock function makes usage of a BEL (\a) character.

usage: alarmclock TIME

TIME is a sleep(1) parameter which tells function how long to wait until raise the alarm.

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printf "%s," "${LIST[@]}" | cut -d "," -f 1-${#LIST[@]}
2012-06-04 14:56:12
User: Valise
Functions: cut printf
0
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Join the content of a bash array with commas

printf reapeats the format as longer as it has arguments. Then the idea is to make cut retain as much fields as we have elements in the array.

As usual with such join/split string manipulation, you have to make sure you don't have conflicts between your separator and your array content.

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find /proc/sys/vm -maxdepth 1 -type f | while read i ; do printf "%-35s\t%s\n" "$i" "$(<$i)" ; done | sort -t/ -k4
2012-05-25 16:34:16
User: SEJeff
Functions: find printf read sort
Tags: Linux sysctl procfs crimsonfu
0
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Pretty print all of the Linux vm sysctls for your viewing pleasure

Sometimes you want to see all of the systcls for a given $thing. I happened to need to easily look at all of the vm sysctls between two boxes and compare them. This is what I came up with.

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members () { dscl . -list /Users | while read user; do printf "$user "; dsmemberutil checkmembership -U "$user" -G "$*"; done | grep "is a member" | cut -d " " -f 1; };
2012-05-20 11:34:33
User: eduo
Functions: cut grep printf read
Tags: function osx group dsmemberutil
-1
Up
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OSX - Function to list all members for a given group

Group membership in OS X is a mish-mash of standards that end up meaning there's almost a half-dozen of ways to belong to a group, what with group inheritance and automatic assignment. This means there's no easy command to find out all groups a user belongs to. The only sensible way then is to list all users and then query each user for membership.

NOTE: This is a function. Once input you can execute it by calling with a groupname.

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printf "%$(tput cols)s\n"|tr ' ' '='
2012-04-21 23:26:55
User: webstandardcss
Functions: printf tr
9
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A line across the entire width of the terminal

Use tput cols to find the width of the terminal and set it as the minimum field width.

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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
2012-04-03 06:41:43
User: hogofogo
Functions: printf read sleep yes
0
Up
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BW gradient
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