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Functions

Commands using printf from sorted by
Terminal - Commands using printf - 166 results
printf "%s," "${LIST[@]}" | cut -d "," -f 1-${#LIST[@]}
2012-06-04 14:56:12
User: Valise
Functions: cut printf
0

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.

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
0

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.

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
-1

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.

printf "%$(tput cols)s\n"|tr ' ' '='
2012-04-21 23:26:55
Functions: printf tr
9

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

yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
_p(){ ps ax |grep $1 |sed '/grep.'"$1"'/d' |while read a;do printf ${a%% *}' ';printf "${a#* }" >&2;printf '\n';done;}
2012-04-01 19:46:19
User: argv
Functions: grep printf ps read sed
0

proc lister

usage: p

proc killer

usage: p patt [signal]

uses only ps, grep, sed, printf and kill

no need for pgrep/pkill (not part of early UNIX)

_p(){

ps ax \

|grep $1 \

|sed '

/grep.'"$1"'/d' \

|while read a;do

printf ${a%% *}' ';

printf "${a#* }" >&2;

printf '\n';

done;

}

p(){

case $# in

0)

ps ax |grep .|less -iE;

;;

1)

_p $1;

;;

[23])

_p $1 2>/dev/null \

|sed '/'"$2"'/!d;

s,.*,kill -'"${3-15}"' &,'|sh -v

;;

esac;

}

alas, can't get this under 255 chars.

flatcap?

_p(){ ps ax |grep $1 |sed '/grep.'"$1"'/d' |while read a;do printf ${a%% *}' ';printf "${a#* }" >&2;printf '\n';done;}
2012-04-01 19:45:17
User: argv
Functions: grep printf ps read sed
0

proc lister

usage: p

proc killer

usage: p patt [signal]

uses only ps, grep, sed, printf and kill

no need for pgrep/pkill (not part of early UNIX)

_p(){

ps ax \

|grep $1 \

|sed '

/grep.'"$1"'/d' \

|while read a;do

printf ${a%% *}' ';

printf "${a#* }" >&2;

printf '\n';

done;

}

p(){

case $# in

0)

ps ax |grep .|less -iE;

;;

1)

_p $1;

;;

[23])

_p $1 2>/dev/null \

|sed '/'"$2"'/!d;

s,.*,kill -'"${3-15}"' &,'|sh -v

;;

esac;

}

alas, can't get this under 255 chars.

flatcap?

find /path/to/dir -iname "*.ext" -print0 | xargs -0 mplayer -really-quiet -cache 64 -vo dummy -ao dummy -identify 2>/dev/null | awk '/ID_LENGTH/{gsub(/ID_LENGTH=/,"")}{SUM += $1}END{ printf "%02d:%02d:%02d\n",SUM/3600,SUM%3600/60,SUM%60}'
2012-03-11 12:28:48
User: DarkSniper
Functions: awk find printf xargs
0

Improvement on Coderjoe's Solution. Gets rid of grep and cut (and implements them in awk) and specifies some different mplayer options that speed things up a bit.

du -k | sort -n | perl -ne 'if ( /^(\d+)\s+(.*$)/){$l=log($1+.1);$m=int($l/log(1024)); printf ("%6.1f\t%s\t%25s %s\n",($1/(2**(10*$m))),(("K","M","G","T","P")[$m]),"*"x (1.5*$l),$2);}' | more
2012-02-07 15:49:19
User: Q_Element
Functions: du perl printf sort
1

This one line Perl script will display the smallest to the largest files sizes in all directories on a server.

genRandomText() { x=({a..z}); for(( i=0; i<$1; i++ )); do printf ${x[$((RANDOM%26))]}; done; printf "\n"; }
2012-01-26 08:19:33
User: uxseven
Functions: printf
0

Here's my version. It's a bit lengthy but I prefer it since it's all Bash.

VAR="%23%21%2fbin%2fbash" ; printf -v VAR "%b" "${VAR//\%/\x}" ; echo $VAR
2012-01-06 22:09:01
User: Corona688
Functions: echo printf
Tags: bash urldecod
5

You can use ordinary printf to convert "%23%21%2fbin%2fbash" into "#!/bin/bash" with no external utilities, by using a little known printf feature -- the "%b" specifier converts shell escapes. Replace % with \x and printf will understand the urlencoded string.

BASH's printf has an extension to set a variable directly, too. So you get to convert urlencoded strings from garble to plaintext in one step with no externals and no backticks.

printf "$PWD/%s\n" *
2011-12-16 13:43:01
User: flatcap
Functions: printf
Tags: printf
3

List the full path of some files.

You can add ".*" on the end if you want to display hidden files.

hex() { printf "%X\n" $1; }
mplayer -endpos 0.1 -vo null -ao null -identify *.avi 2>&1 |grep ID_LENGTH |cut -d = -f 2|awk '{SUM += $1} END { printf "%d:%d:%d\n",SUM/3600,SUM%3600/60,SUM%60}'
awk 'BEGIN{FS=":"; print "digraph{"}{split($4, a, ","); for (i in a) printf "\"%s\" [shape=box]\n\"%s\" -> \"%s\"\n", $1, a[i], $1}END{print "}"}' /etc/group|display
2011-12-04 01:56:44
Functions: awk printf
19

Parses /etc/group to "dot" format and pases it to "display" (imagemagick) to show a usefull diagram of users and groups (don't show empty groups).

human_filesize() { awk -v sum="$1" ' BEGIN {hum[1024^3]="Gb"; hum[1024^2]="Mb"; hum[1024]="Kb"; for (x=1024^3; x>=1024; x/=1024) { if (sum>=x) { printf "%.2f %s\n",sum/x,hum[x]; break; } } if (sum<1024) print "1kb"; } '}
2011-12-02 18:21:20
User: ArtBIT
Functions: awk printf
2

Converts a number of bytes provided as input, to a human readable number.

myhex=$(printf '%02X' ${myip//./ };)
2011-11-30 15:12:28
Functions: printf
Tags: IP hex printf octet
2

Converts IP octets to hex using printf command. Useful for generating pxeboot aliases in the pxelinux.cfg folder.

find . -type f -exec awk '/linux/ { printf "%s %s: %s\n",FILENAME,NR,$0; }' {} \;
while true; do cat /proc/net/dev; sleep 1; done | awk -v dc="date \"+%T\"" '/eth0/{i = $2 - oi; o = $10 - oo; oi = $2; oo = $10; dc|getline d; close(dc); if (a++) printf "%s %8.2f KiB/s in %8.2f KiB/s out\n", d, i/1024, o/1024}'
2011-11-21 05:24:44
Functions: awk cat printf sleep
Tags: awk sh
10

poorman's ifstat using just sh and awk. You must change "eth0" with your interface's name.

awk '{ printf "%.2f", $2/1024/1024 ; exit}' /proc/meminfo
whichpath() { local -A path; local c p; for c; do p=$(type -P "$c"); p=${p%/*}; path[${p:-/}]=1; done; local IFS=:; printf '%s\n' "${!path[*]}"; }
2011-09-16 15:55:15
User: RanyAlbeg
Functions: printf type
0

I find it useful when I want to add another crontab entry and I need to specify the appropriate PATH.

I give ''whichpath'' a list of programs that I use inside my script and it gives me the PATH I need to use for this script.

''whichpath'' uses associative array, therefore you should have Bash v4 in order to run it.

See sample output.

i=60;while [ $i -gt 0 ];do if [ $i -gt 9 ];then printf "\b\b$i";else printf "\b\b $i";fi;sleep 1;i=`expr $i - 1`;done
SCALE=3; WIDTHL=10; WIDTHR=60; BAR="12345678"; BAR="${BAR//?/==========}"; while read LEFT RIGHT rest ; do RIGHT=$((RIGHT/SCALE)); printf "%${WIDTHL}s: %-${WIDTHR}s\n" "${LEFT:0:$WIDTHL}" "|${BAR:0:$RIGHT}*"; done < dataset.dat
2011-08-22 19:35:21
User: andreasS
Functions: printf read
0

WIDTHL=10 and WIDTHR=60 are setting the widths of the left and the right column/bar. BAR="12345678" etc. is used to create a 80 char long string of "="s. I didn't know any shorter way.

If you want to pipe results into it, wrap the whole thing in ( ... )

I know that printing bar graphs can be done rather easily by other means. Here, I was looking for a Bash only variant.

isgd () { curl 'http://is.gd/create.php?format=simple&url='"$1" ; printf "\n" }
2011-08-14 23:31:39
User: dbbolton
Functions: printf
Tags: curl shorturl url
1

Check the API. You shouldn't need sed. The print-newline at the end is to prevent zsh from inserting a % after the end-of-output.

Also works with http://v.gd

arp-scan -I eth0 -l | perl -ne '/((\d{1,3}\.){3}\d{1,3})/ and $ip=$1 and $_=`nmblookup -A $ip` and /([[:alnum:]-]+)\s+<00>[^<]+<ACTIVE>/m and printf "%15s %s\n",$ip,$1'