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Commands using read from sorted by
Terminal - Commands using read - 299 results
A=1;B=100;X=0;C=0;N=$[$RANDOM%$B+1];until [ $X -eq $N ];do read -p "N between $A and $B. Guess? " X;C=$(($C+1));A=$(($X<$N?$X:$A));B=$(($X>$N?$X:$B));done;echo "Took you $C tries, Einstein";
2009-12-16 13:24:23
User: rodolfoap
Functions: read
Tags: Game

Felt like I need to win the lottery, and wrote this command so I train and develop my guessing abilities.

while [ 1 ]; do banner 'ze missiles, zey are coming! ' | while IFS="\n" read l; do echo "$l"; sleep 0.01; done; done
2009-12-14 07:40:07
User: craigds
Functions: banner echo read sleep

Displays a scrolling banner which loops until you hit Ctrl-C to terminate it.

Make sure you finish your banner message with a space so it will loop nicely.

while read str; do echo "$((++i)) - $str"; done < infile
2009-12-09 15:11:25
User: putnamhill
Functions: echo read
Tags: bash

Hi glaudiston, you can save a few chars by leaving out cat and pipe and still enjoy the added flexibility.

cat infile | while read str; do echo "$((++i)) - $str" ; done;
2009-12-09 14:05:09
User: glaudiston
Functions: cat echo read

Yep, is hard, but is a way more flexible using pipe.

while read n; do host $n; done < list
while IFS=: read u x; do passwd -e "$u"; done < /etc/passwd
2009-11-20 21:49:34
User: cfajohnson
Functions: passwd read

This assumes that te original's 'passwd -e' forces a user to change password; it doesn't in the versions I have.

find <path> -name "*.tgz" -or -name "*.tar.gz" | while read file; do echo "$file: "; tar -tzf $file; done
2009-11-10 20:39:04
User: polaco
Functions: echo find read tar
Tags: find tar list

This script will list all the files in the tarballs present on any folder or subfolder of the provided path. The while loop is for echoing the file name of the tarball before listing the files, so the tarball can be identified

find -name '*.avi' | while read i ; do echo $(mplayer -identify -frames 0 -vo null -nosound "$i" 2>&1 | grep ID_LENGTH | cut -d= -f2)" ""$i" ;done | sort -k1 -r -n | sed 's/^\([^\ ]*\)\ \(.*\)$/\2:\1/g'
2009-11-09 17:14:59
User: ZungBang
Functions: cut echo find grep read sed sort

handles file names with spaces and colons, fixes sort (numeric!), uses mplayer, same output format as other alternatives

find . -type f | while read f; do chmod -x "$f"; done
read -sn 1 -p 'Press any key to continue...';echo
read -sn 1 -p "Press any key to continue..."
git ls-files | while read i; do git blame $i | sed -e 's/^[^(]*(//' -e 's/^\([^[:digit:]]*\)[[:space:]]\+[[:digit:]].*/\1/'; done | sort | uniq -ic | sort -nr
2009-10-25 09:40:01
User: pipping
Functions: read sed sort uniq
Tags: statistics git

You'll run into trouble if you have files w/ missing newlines at the end. I tried to use

PAGER='sed \$q' git blame

and even

PAGER='sed \$q' git -p blame

to force a newline at the end, but as soon as the output is redirected, git seems to ignore the pager.

seg() { echo -e "$1" | while read LINE; do for b in $(seq 10); do echo $LINE.$b; done; done; }
ord () { seq 1 127 | while read i; do echo `chr $i` $i; done | grep "^$1 " | cut -c '3-' }
2009-10-16 21:54:01
User: infinull
Functions: cut echo grep read seq

uses the previous "chr" function and uses it to create the inverse function "ord" by brute force.

It's slow, It's inelegant, but it works.

I thought I needed ord/chr to do a cartesian cipher in shell script a whie ago, but eventualy I realized I could get fancy with tr and do the same thing...

dpkg --get-selections | cut -f1 | while read pkg; do dpkg -L $pkg | xargs -I'{}' bash -c 'if [ ! -d "{}" ]; then echo "{}"; fi' | tr '\n' '\000' | du -c --files0-from - | tail -1 | sed "s/total/$pkg/"; done
2009-10-12 14:57:54
User: pykler
Functions: bash cut du echo read sed tail tr xargs
Tags: Debian wajig

Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the

| sort -rn

which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side

Also you may need to run this as root as some files can only be checked by du if you can read them ;)

cat file.txt | while read line; do printf "%7.2f -> %7.2f\n" $line; done
beepwhenup () { echo 'Enter host you want to ping:'; read PHOST; if [[ "$PHOST" == "" ]]; then exit; fi; while true; do ping -c1 -W2 $PHOST 2>&1 >/dev/null; if [[ "$?" == "0" ]]; then for j in $(seq 1 4); do beep; done; ping -c1 $PHOST; break; fi; done; }
2009-09-24 18:11:10
Functions: echo host ping read seq
Tags: ping beep

After this, just type:


You need to install "beep" before this would make the beep sound.

Save it in your .profile if you want to use it later

WARNING: this command won't exit until it is successful. You won't be able to CONTROL+C out of it.

tar -cvf /dev/null . | while read i; do ls -l $i; done
2009-09-16 16:59:15
User: lbonanomi
Functions: ls read tar

I find the ouput of ls -lR to be un-satisfying (why is the path data up there?) and find syntax to be awkward. Running 'du -a' means you will have likely to trim-off filesize data before feeding filenames to the next step in the pipe.

find repMainPath -maxdepth 1 -mindepth 1 -type d | while read dir; do echo processing $dir; sudo svnadmin dump --deltas $dir >dumpPath/`basename $dir`; done
2009-09-15 20:14:51
User: Marco
Functions: dump echo find read sudo
Tags: bash svn

This command dumps all SVN repositories inside of folder "repMainPath" (not recursively) to the folder "dumpPath", where one dump file will be created for each SVN repository.

find -type f |while read a;do [ "`head -c3 -- "${a}"`" == $'\xef\xbb\xbf' ] && echo "Match: ${a}";done
function sepath { echo $PATH |tr ":" "\n" |sort -u |while read L ; do cd "$L" 2>/dev/null && find . \( ! -name . -prune \) \( -type f -o -type l \) 2>/dev/null |sed "s@^\./@@" |egrep -i "${*}" |sed "s@^@$L/@" ; done ; }
2009-09-11 15:03:22
User: mobidyc
Functions: cd echo egrep find read sed sort tr
Tags: bash ksh PATH

search argument in PATH

accept grep expressions

without args, list all binaries found in PATH

yes "$(seq 1 255)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
du -a --max-depth=1 | sort -n | cut -d/ -f2 | sed '$d' | while read i; do if [ -f $i ]; then du -h "$i"; else echo "$(du -h --max-depth=0 "$i")/"; fi; done
2009-09-03 20:43:43
User: nickwe
Functions: cut du echo read sed sort

Based on the MrMerry one, just add some visuals to differentiate files and directories

find . -maxdepth 1 -type d|xargs du -a --max-depth=0|sort -rn|cut -d/ -f2|sed '1d'|while read i;do echo "$(du -h --max-depth=0 "$i")/";done;find . -maxdepth 1 -type f|xargs du -a|sort -rn|cut -d/ -f2|sed '$d'|while read i;do du -h "$i";done
2009-09-03 20:33:21
User: nickwe
Functions: cut du echo find read sed sort xargs

Based on the MrMerry one, just add some visuals and sort directory and files

while read server; do ssh -n user@$server "command"; done < servers.txt
2009-08-29 06:52:34
User: sharfah
Functions: read ssh

The important thing to note in this command, is the "-n" flag.