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Commands using read

Commands using read from sorted by
Terminal - Commands using read - 251 results
awk -F":" '{ print $1 }' /etc/passwd | while read UU ; do STATUS=$(passwd -S ${UU} | grep locked 2>/dev/null) ; if [[ ! -z ${STATUS} ]] ; then echo "Account ${UU} is locked." ; fi ; done
2009-12-18 14:28:15
User: unixhome
Functions: awk echo grep passwd read
0
Up
Down
Sometimes you just want a quick way to find out if a certain user account is locked [Linux].
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
A=1;B=100;X=0;C=0;N=$[$RANDOM%$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
13
Up
Down
Numbers guessing game

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

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: bash read ascii loop banner
10
Up
Down
bash screensaver (scrolling ascii art with customizable message)

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.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while read str; do echo "$((++i)) - $str"; done < infile
2009-12-09 15:11:25
User: putnamhill
Functions: echo read
Tags: bash
-1
Up
Down
prints line numbers

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

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cat infile | while read str; do echo "$((++i)) - $str" ; done;
2009-12-09 14:05:09
User: glaudiston
Functions: cat echo read
-1
Up
Down
prints line numbers

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

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while read n; do host $n; done < list
2009-12-07 18:03:20
User: putnamhill
Functions: host read
Tags: bash host
1
Up
Down
Ruby - nslookup against a list of IP`s or FQDN`s

This version uses host and no ruby.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while IFS=: read u x; do passwd -e "$u"; done < /etc/passwd
2009-11-20 21:49:34
User: cfajohnson
Functions: passwd read
0
Up
Down
force change password for all user

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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
-2
Up
Down
List files in tarballs

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

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2
Up
Down
Sort movies by length, longest first

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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -type f | while read f; do chmod -x "$f"; done
2009-11-09 04:30:44
User: alesplin
Functions: chmod find read
-4
Up
Down
Remove executable bit from all files in the current directory recursively, excluding other directories

I hate -exec with find, and this pattern quickly expands to other tasks.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
read -sn 1 -p 'Press any key to continue...';echo
2009-11-07 03:05:21
User: arcege
Functions: read
Tags: bash read
6
Up
Down
Press Any Key to Continue
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
read -sn 1 -p "Press any key to continue..."
2009-11-05 21:53:23
User: kalaxy
Functions: read
22
Up
Down
Press Any Key to Continue

Halt script progress until a key has been pressed.

Source: http://bash-hackers.org/wiki/doku.php/mirroring/bashfaq/065

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
-1
Up
Down
Prints per-line contribution per author for a GIT repository

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.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
seg() { echo -e "$1" | while read LINE; do for b in $(seq 10); do echo $LINE.$b; done; done; }
2009-10-20 17:45:43
User: Waldirio
Functions: echo read seq
Tags: while for
0
Up
Down
Command to build one or more network segments - with while
Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
0
Up
Down
Get decimal ascii code from character

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...

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
5
Up
Down
List your largest installed packages.

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 ;)

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat file.txt | while read line; do printf "%7.2f -> %7.2f\n" $line; done
2009-10-06 07:09:23
User: opexxx
Functions: cat printf read
0
Up
Down
Bashbuiltin printf
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
beepwhenup () { echo 'Enter host you want to ping:'; read PHOST; if [[ "$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
User: linuxrawkstar
Functions: echo host ping read seq
Tags: ping beep
2
Up
Down
ping a host until it responds, then play a sound, then exit

After this, just type:

beepwhenup

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.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tar -cvf /dev/null . | while read i; do ls -l $i; done
2009-09-16 16:59:15
User: lbonanomi
Functions: ls read tar
-8
Up
Down
ls -lR with a full path

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.

Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2
Up
Down
Archive all SVN repositories in platform indepenent form

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.

Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find -type f |while read a;do [ "`head -c3 -- "${a}"`" == $'\xef\xbb\xbf' ] && echo "Match: ${a}";done
2009-09-15 08:43:21
User: pfredrik
Functions: echo find read
0
Up
Down
Find UTF-8 text files misinterpreted as ISO 8859-1 due to Byte Order Mark (BOM) of the Unicode Standard.

Same thing, only "head" instead of grep/egrep..

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
-1
Up
Down
search for a file in PATH

search argument in PATH

accept grep expressions

without args, list all binaries found in PATH

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
yes "$(seq 1 255)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done
2009-09-05 04:01:23
User: unixmonkey4581
Functions: printf read sleep yes
10
Up
Down
cycle through a 256 colour palette

Rainbow, instead of greys

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: bash sort sed echo du read while cut
3
Up
Down
Ultimate current directory usage command

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

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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
Tags: bash sort sed echo find xargs read while cut
2
Up
Down
Ultimate current directory usage command

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

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate