Commands using read (338)


  • 5
    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
    kev · 2012-04-09 15:22:19 2
  • Old snapshots can cause problems. It's best to remove them when finished. I use this script to remove all snapshots. The "while read" command is necessary because my vm names contain spaces. The "time" command reports how long the process runs.


    4
    time vmware-cmd -l | while read x; do printf "$x"; vmware-cmd "$x" removesnapshots; done
    jcgam69 · 2009-02-26 18:51:29 5
  • Obviously, you can replace 'man' command with any command in this command line to do useful things. I just want to mention that there is a way to list all the commands which you can execute directly without giving fullpath. Normally all important commands will be placed in your PATH directories. This commandline uses that variable to get commands. Works in Ubuntu, will work in all 'manpage' configured *nix systems. Show Sample Output


    4
    find `echo "${PATH}" | tr ':' ' '` -type f | while read COMMAND; do man -f "${COMMAND##*/}"; done
    mohan43u · 2009-06-13 19:56:24 4
  • Waiting for a key stroke. You can use this with a ";" behind to build a command chain. Show Sample Output


    4
    read -p "Press enter to continue.."
    brubaker · 2010-04-13 13:05:09 4
  • in "a.html", find all images referred as relative URI in an HTML file by "src" attribute of "img" element, replace them with "data:" URI. This useful to create single HTML file holding all images in it, as a replacement of the IE-created .mht file format. The generated HTML works fine on every other browser except IE, as well as many HTML editors like kompozer, while the .mht format only works for IE, but not for every other browser. Compare to the KDE's own single-file-web-page format "war" format, which only opens correctly on KDE, the HTML file with "data:" URI is more universally supported. The above command have many bugs. My commandline-fu is too limited to fix them: 1. it assume all URLs are relative URIs, thus works in this case: <img src="images/logo.png"/> but does not work in this case: <img src="http://www.my_web_site.com/images/logo.png" /> This may not be a bug, as full URIs perhaps should be ignored in many use cases. 2. it only work for images whoes file name suffix is one of .jpg, .gif, .png, albeit images with .jpeg suffix and those without extension names at all are legal to HTML. 3. image file name is not allowed to contain "(" even though frequently used, as in "(copy of) my car.jpg". Besides, neither single nor double quotes are allowed. 4. There is infact a big flaw in this, file names are actually used as regular expression to be replaced with base64 encoded content. This cause the script to fail in many other cases. Example: 'D:\images\logo.png', where backward slash have different meaning in regular expression. I don't know how to fix this. I don't know any command that can do full text (no regular expression) replacement the way basic editors like gedit does. 5. The original a.html are not preserved, so a user should make a copy first in case things go wrong.


    4
    grep -ioE "(url\(|src=)['\"]?[^)'\"]*" a.html | grep -ioE "[^\"'(]*.(jpg|png|gif)" | while read l ; do sed -i "s>$l>data:image/${l/[^.]*./};base64,`openssl enc -base64 -in $l| tr -d '\n'`>" a.html ; done;
    zhangweiwu · 2010-05-05 14:07:51 7
  • wget --user=username --password="$password" http://example.org/ Instead of hiding commands entirely from history, I prefer to use "read" to put the password into a variable, and then use that variable in the commands instead of the password. Without the "-e" and "-s" it should work in any bourne-type shell, but the -s is what makes sure the password doesn't get echoed to the screen at all. (-e makes editing work a bit better)


    4
    read -e -s -p "Password: " password
    freiheit · 2010-08-18 17:53:27 3
  • Should be a bit more portable since echo -e/n and date's -Ins are not. Show Sample Output


    4
    tail -f file | while read line; do printf "$(date -u '+%F %T%z')\t$line\n"; done
    derekschrock · 2010-11-24 05:50:12 2
  • Like 7171, but fixed typo, uses fewer variables, and even more cryptic! Show Sample Output


    4
    read -a A<<<".*.**..*....*** 8 9 5 10 6 0 2 11 7 4";for C in `date +"%H%M"|fold -w1`;do echo "${A:${A[C+1]}:4}";done
    __ · 2010-12-02 22:04:49 3
  • 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


    4
    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
    SQUIIDUX · 2012-04-22 01:51:30 3
  • This assumes you have the package installed necessary for converting WMF files. On my Ubuntu box, this is libwmf-bin. I used this command, as libwmf is not on my wife's iMac, so I archived the directories containing the WMF files from OS X, ran them on my Ubuntu box, archived the resulting SVGs, and sent them back to her. Quick, simple and to the point. Searches directories recursively looking for extensions ignoring case. This is much more readable and clean than -exec for find. The while loop also gives further flexibility on complex logic. Also, although there is 'wmf2svg --auto', it expects lowercase extensions, and not uppercase. Because I want to ignore case, I need to use the -o option instead. Works in ZSH and BASH. Haven't tested in other shells.


    3
    find . -type f -iname '*.wmf' | while read FILE; do FILENAME="${FILE%.*}"; wmf2svg -o ${FILENAME}.svg $FILE; done
    atoponce · 2009-03-07 22:21:01 9
  • Reads a username from Show Sample Output


    3
    read -p 'Username: ' u;sudo -H -u $u xauth add $(xauth list|grep :$(echo ${DISPLAY: -4:2}));sudo su - $u
    vutcovici · 2009-04-02 13:24:53 6
  • connects to all the screen instances running.


    3
    screen -ls | grep pts | gawk '{ split($1, x, "."); print x[1] }' | while read i; do gnome-terminal -e screen\ -dx\ $i; done
    microft · 2009-04-22 10:36:39 9

  • 3
    find . -name "*.jar" | while read file; do echo "Processing ${file}"; jar -tvf $file | grep "Foo.class"; done
    sharfah · 2009-05-20 17:33:17 3
  • Find Word docs by filename in the current directory, convert each of them to plain text using antiword (taking care of spaces in filenames), then grep for a search term in the particular file. (Of course, it's better to save your data as plain text to make for easier grepping, but that's not always possible.) Requires antiword. Or you can modify it to use catdoc instead.


    3
    find . -iname '*filename*.doc' | { while read line; do antiword "$line"; done; } | grep -C4 search_term;
    Ben · 2009-07-28 15:49:58 3
  • Based on the MrMerry one, just add some visuals to differentiate files and directories


    3
    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
    nickwe · 2009-09-03 20:43:43 2
  • Create a text file called domainlist.txt with a domain per line, then run the command above. All registries are a little different, so play around with the command. Should produce a list of domains and their expirations date. I am responsible for my companies domains and have a dozen or so myself, so this is a quick check if I overlooked any.


    3
    cat domainlist.txt | while read line; do echo -ne $line; whois $line | grep Expiration ; done | sed 's:Expiration Date::'
    netsaint · 2010-05-02 06:49:09 3
  • This shows every bit of information that stat can get for any file, dir, fifo, etc. It's great because it also shows the format and explains it for each format option. If you just want stat help, create this handy alias 'stath' to display all format options with explanations. alias stath="stat --h|sed '/Th/,/NO/!d;/%/!d'" To display on 2 lines: ( F=/etc/screenrc N=c IFS=$'\n'; for L in $(sed 's/%Z./%Z\n/'<<<`stat --h|sed -n '/^ *%/s/^ *%\(.\).*$/\1:%\1/p'`); do G=$(echo "stat -$N '$L' \"$F\""); eval $G; N=fc;done; ) For a similarly powerful stat-like function optimized for pretty output (and can sort by any field), check out the "lll" function http://www.commandlinefu.com/commands/view/5815/advanced-ls-output-using-find-for-formattedsortable-file-stat-info From my .bash_profile -> http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    3
    statt(){ C=c;stat --h|sed '/Th/,/NO/!d;/%/!d'|while read l;do p=${l/% */};[ $p == %Z ]&&C=fc&&echo ^FS:^;echo "`stat -$C $p \"$1\"` ^$p^${l#%* }";done|column -ts^; }
    AskApache · 2010-06-11 23:31:03 2
  • Revised approach to and3k's version, using pipes and read rather than command substitution. This does not require fiddling with IFS when paths have whitespace, and does not risk hitting command-line size limits. It's less verbose on the missing files, but it stops iterating at the first file that's missing, so it should be definitely faster. I expanded all the qlist options to be more self-describing.


    3
    emerge -av1 `qlist --installed --nocolor | uniq | while read cp; do qlist --exact $cp | while read file; do test -e $file || { echo $cp; echo "$cp: missing $file (and maybe more)" 1>&2; break; }; done; done`
    Flameeyes · 2010-07-04 19:55:42 4
  • Similar to xargs -i, but works with builtin bash commands (rather than running "bash -c ..." through xargs)


    3
    xargsb() { while read -r cmd; do ${@//'{}'/$cmd}; done; }
    BobbyTables · 2010-09-28 06:35:39 5
  • This version works across on all POSIX compliant shell variants.


    3
    Confirm() { echo -n "$1 [y/n]? " ; read reply; case $reply in Y*|y*) true ;; *) false ;; esac }
    eikenberry · 2010-11-22 16:54:16 2

  • 3
    bargs { while read i; do "$@" "$i"; done }
    wytten · 2011-01-06 19:25:43 3
  • basic find implementation for systems that don't actually have find, like an android console without busybox installed.


    3
    find (); { ls $1 | while read line; do [[ -d $1/$line ]] && find $1/$line $2 || echo $1/$line | grep $2; done; }
    a8ksh4 · 2013-07-28 22:21:39 19
  • Creates an incremental snapshot of individual folders.


    3
    find /mnt/storage/profiles/ -maxdepth 1 -mindepth 1 -type d | while read d; do tarfile=`echo "$d" | cut -d "/" -f5`; destdir="/local/backupdir/"; tar -g "$destdir"/"$tarfile".snar -czf "$destdir"/"$tarfile"_`date +%F`.tgz -P $d; done
    jaimerosario · 2013-12-05 19:20:31 9
  • Creates a temporary ram partition To use: ram 3 to make a 3gb partition (Defaults to 1gb) Show Sample Output


    3
    ram() { mt=/mnt/ram && grep "$mt" < /proc/mts > /dev/null; if [ $? -eq 0 ] ; then read -p"Enter to Remove Ram Partition ";sudo umount "$mt" && echo $mt 0; else sudo mt -t tmpfs tmpfs "$mt" -o size=$(( ${1:-1} * 1024 ))m && echo $mt '-' "${1:-1}"gb; fi; }
    snipertyler · 2013-12-13 05:22:02 3
  • Useful to add a timestamp to every line printed to stdout. You can use `-Ins` instead of `-Iseconds` if you want more precision. Show Sample Output


    3
    any command | while read line; do echo "[`date -Iseconds`] $line"; done
    ayosec · 2014-02-07 22:27:29 3
  •  < 1 2 3 4 5 >  Last ›

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands


Check These Out

Get your commandlinefu points (upvotes - downvotes)
This will calculate the your commandlinefu votes (upvotes - downvotes). Hopefully this will boost my commandlinefu points.

Optimize Xsane PDFs
Xsane produces PDFs that are too large - particularly multipage PDFs. This command compresses them. If you do not use A4, remove the -sPAPERSIZE flag.

Remove security limitations from PDF documents using ghostscript (for Windows)
#4345 also works under windows

Using mplayer to play the audio only but suppress the video

tar+pbzip2 a dir

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Your GeoIP location on Google Maps

Print permanent subtitles on a video
It prints myvideo.srt subtitle files in myvideo.avi, saving it in myvideo_subtitled.avi

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Get the Volume labels all bitlocker volumes had before being encrypted
Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before.


Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: