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Commands using read from sorted by
Terminal - Commands using read - 279 results
lsof -p `pidof pidgin` | awk '{ print $9 }'|egrep `hostname` | grep -o ">[^:]\+:" | tr -d ":>" | while read line; do host $line; done;
ls *.png | while read line; do pngcrush -brute $line compressed/$line; done
2012-07-17 20:20:49
User: waffleboi9
Functions: ls read
0

Nothing too magical here, just uses pngcrush to losslessly compress all your pngs!

svn status | grep "^M" | while read entry; do file=`echo $entry | awk '{print $2}'`; echo $file; svn revert $file; done
2012-06-17 16:01:06
User: wsams
Functions: awk echo grep read
0

This command allows you to revert every modified file one-by-one in a while loop, but also after "echo $file;" you can do any sort of processing you might want to add before the revert happens.

read -s p && echo -n $p | md5sum;p=
2012-06-08 13:50:50
User: hoodie
Functions: echo read
1

create and md5 sum of your password without it showing up in your terminal or history.

Afterwards we overwrite the $p variable (thx to bazzargh)

#!/bin/zsh SHL='\\e[0;31m' EHL='\\e[0m' while read line; do TEXT=$line for SSTR in $*; do TEXT=$(echo $TEXT | sed -e "s:$SSTR:${SHL}${SSTR}${EHL}:g") done echo -e $TEXT done
find /proc/sys/vm -maxdepth 1 -type f | while read i ; do printf "%-35s\t%s\n" "$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.

while true; do sudo cat /dev/input/mouse0|read -n1;streamer -q -o /tmp/cam.jpeg -s 640x480 > /dev/null 2>&1; sleep 10;done
2012-04-22 01:51:30
User: SQUIIDUX
Functions: cat read sleep sudo
Tags: cat streamer
4

This takes a webcam picture every everytime the mouse is moved (waits 10 seconds between checking for movement) and stores the picture wherever you want it.

Ideas:

Use in conjunction with a dropbox type application to see who is using your computer

Use /dev/input/mice if /dev/input/mouse* doesn't work

Use the bones of this to make a simple screensaver

read -p "Question that you want an answer to?" yn
jobs | grep -o "[0-9]" | while read j; do kill %$j; done
2012-04-12 17:29:58
User: haggen
Functions: grep jobs kill read
0

List background jobs, grep their number - not process id - and then kill them

paste <(seq 7 | shuf | tr 1-7 A-G) <(seq 7 | shuf) | while read i j; do play -qn synth 1 pluck $i synth 1 pluck mix $2; done
yes "$(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?

svnll(){svn log "$@"|( read; while true; do read h||break; read; m=""; while read l; do echo "$l" | grep -q '^[-]\+$'&&break; [ -z "$m" ] && m=$l; done; echo "$h % $m" | sed 's#\(.*\) | \(.*\) | \([-0-9 :]\{16\}\).* % \(.*\)#\1 \2 (\3) \4#'; done)}
2012-03-25 20:39:05
User: vhotspur
Functions: echo grep read sed
Tags: log subversion
0

Emulate (more or less) Git equivalent of

git log --format='tformat:%h %an (%cr) %s'
find . -iname '*.zip' | while read file; do unzip -l "$file" | grep -q [internal file name] && echo $file; done
2012-03-23 18:08:35
User: ricardofunke
Functions: echo file find grep read
1

This command find which of your zip (or jar) files (when you have lots of them) contains a file you're searching for. It's useful when you have a lot of zip (or jar) files and need to know in which of them the file is archived.

It's most common with .jar files when you have to know which of the .jar files contains the java class you need.

To find in jar files, you must change "zip" to "jar" in the "find" command. The [internal file name] must be changed to the file name you're searching that is archived into one of the zip/jar files.

Before run this command you must step into the directory that contains the zip or jar files.

lsgrp() { read GID USERS <<< "$(grep "^$1:" /etc/group | cut -d: -f3,4 | tr ':,' ' ')" ; echo -e "${USERS// /\n}" | egrep -v "^($1)?$" ; egrep :[0-9]+:$GID: /etc/passwd | cut -d: -f1 ; }
2012-03-16 09:57:33
User: livibetter
Functions: cut echo egrep read
0

I can't find the lid command on my system, there is also another complied program: http://xyne.archlinux.ca/projects/lsgrp/

seq 1 1000000 | while read i; do echo -en "\r$i"; done
echo "Click a window to start recording"; read x y W H <<< `xwininfo | grep -e Width -e Height -e Absolute | grep -oE "[[:digit:]]{1,}" | tr "\n" " "`; ffmpeg -f alsa -ac 1 -i pulse -f x11grab -s ${W}x${H} -r 25 -i :0.0+${x},${y} -sameq output.mkv
2012-03-14 19:42:28
User: joseCanciani
Functions: echo grep read tr
1

The script gets the dimensions and position of a window and calls ffmpeg to record audio and video of that window. It saves it to a file named output.mkv

while read l; do echo -e "$l"; done <1.txt >2.txt
2012-03-13 14:27:49
User: knoppix5
Functions: echo read
Tags: bash read
5

Bash only, no sed, no awk. Multiple spaces/tabs if exists INSIDE the line will be preserved. Empty lines stay intact, except they will be cleaned from spaces and tabs if any available.

mysql -BNe "SELECT id FROM processlist WHERE user = 'redmine';" information_schema | while read id; do mysqladmin kill $id; done
2012-03-09 17:37:23
User: anarcat
Functions: kill read
Tags: mysql kill BOFH
0

Kills all the threads from the user provided in the WHERE request.

Can be refined through the SQL request, of course, see http://dev.mysql.com/doc/refman/5.1/en/processlist-table.html for the available columns.

for i in $(seq 1 20); do while read line; do echo "$i: $line"; done<$i.py; done
lsof -n -P|grep FlashXX|awk '{ print "/proc/" $2 "/fd/" substr($4, 1, length($4)-1) }'|while read f;do newname=$(exiftool -FileModifyDate -FileType -t -d %Y%m%d%H%M%S $f|cut -f2|tr '\n' '.'|sed 's/\.$//');echo "$f -> $newname";cp $f ~/Vids/$newname;done
2012-02-25 01:49:45
User: mhs
Functions: awk cp cut echo grep read sed tr
8

Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.

while read ; do python <script> ; done
2012-02-23 22:29:09
User: Zulu
Functions: python read
-2

Very useful for test a script. After launch this command, you only have to press ENTER for launch your script again. I work with screen and tape ENTER instead of '!!'+ENTER

If you break your script with CTRL-C, it will wait for press ENTER and will re-launch

You can write like it : while read -p "Press ENTER" ; do python ; done

ls|grep .mp3 >list.txt; while read line; do newname=`echo $line|sed 's/\ /-/g'|sort`; newname=`echo $newname|tr -s '-' `; echo $newname; echo $newname>> tracklist.txt;mv "$line" "$newname"; done <list.txt; rm list.txt