Commands using read (313)

  • 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.


    1
    find . -iname '*.zip' | while read file; do unzip -l "$file" | grep -q [internal file name] && echo $file; done
    ricardofunke · 2012-03-23 18:08:35 3
  • I can't find the lid command on my system, there is also another complied program: http://xyne.archlinux.ca/projects/lsgrp/


    0
    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 ; }
    livibetter · 2012-03-16 09:57:33 0

  • 0
    seq 1 1000000 | while read i; do echo -en "\r$i"; done
    evandrix · 2012-03-15 14:13:04 2
  • 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 Show Sample Output


    1
    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
    joseCanciani · 2012-03-14 19:42:28 0
  • 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.


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


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

  • -2
    for i in $(seq 1 20); do while read line; do echo "$i: $line"; done<$i.py; done
    evandrix · 2012-03-09 01:06:50 0
  • 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.


    8
    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
    mhs · 2012-02-25 01:49:45 1
  • 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


    -2
    while read ; do python <script> ; done
    Zulu · 2012-02-23 22:29:09 2
  • for music file of mp3.zing.vn Show Sample Output


    0
    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
    hieuht · 2012-02-16 08:33:14 9
  • I have used single packet, and in a silent mode with no display of ping stats. This is with color and UI improvement to the http://www.commandlinefu.com/commands/view/10220/check-if-a-machine-is-online. It is as per the enhancements suggested. Show Sample Output


    1
    echo -n "IP Address or Machine Name: "; read IP; ping -c 1 -q $IP >/dev/null 2>&1 && echo -e "\e[00;32mOnline\e[00m" || echo -e "\e[00;31mOffline\e[00m"
    crlf · 2012-02-09 07:00:03 1
  • This variation can handle file paths containing spaces.


    1
    fdupes -R -1 path | while read -r line; do (echo $line | xargs -n 1 | (first="true"; firstfile=""; while read file; do if [ "$first" == "true" ]; then first="false"; firstfile=$file; else ln --force "$firstfile" "$file"; fi; done)); done
    eclewis · 2012-02-01 15:08:18 0

  • 1
    fdupes -r -1 Neu | while read line; do j="0"; buf=""; for file in ${line[*]}; do if [ "$j" == "0" ]; then j="1"; buf=$file; else ln -f $buf $file; fi; done; done
    bugmenot · 2012-01-20 22:26:54 0
  • full command: for fn in xkcd*.png xkcd*.jpg; do; echo $fn; read xw xh <<<$(identify -format '%w %h' $fn); nn="$(echo $fn | sed 's/xkcd-\([0-9]\+\)-.*/\1/')"; wget -q -O xkcd-${nn}.json http://xkcd.com/$nn/info.0.json; tt="$(sed 's/.*"title": "\([^"]*\)", .*/\1/' xkcd-${nn}.json)"; at="$(sed 's/.*alt": "\(.*\)", .*/\1/' xkcd-${nn}.json)"; convert -background white -fill black -font /usr/share/fonts/truetype/freefont/FreeSansBold.ttf -pointsize 26 -size ${xw}x -gravity Center caption:"$tt" tt.png; convert -background '#FFF9BD' -border 1x1 -bordercolor black -fill black -font /usr/share/fonts/truetype/freefont/FreeSans.ttf -pointsize 16 -size $(($xw - 2))x -gravity Center caption:"$at" at.png; th=$(identify -format '%h' tt.png); ah=$(identify -format '%h' at.png); convert -size ${xw}x$(($xh+$th+$ah+5)) "xc:white" tt.png -geometry +0+0 -composite $fn -geometry +0+$th -composite at.png -geometry +0+$(($th+$xh+5)) -composite ${fn%\.*}_cmp.png; echo -e "$fn $nn $xw $xh $th $ah \n$tt \n$at\n"; done this assumes that all comics are saved as xkcd-[number]-[title].{png|jpg}. it will then download the title and alt-text, create pictures from them, and put everything together in a new png-file. it's not perfect, but it worked for nearly all my comics. it uses the xkcd-json-interface. though it's poorly written, it doesn't completely break on http://xkcd.com/859/


    -2
    for fn in xkcd*.png xkcd*.jpg; do echo $fn; read xw xh <<<$(identify -format '%w %h' $fn); nn="$(echo $fn | sed 's/xkcd-\([^-]\+\)-.*/\1/')"; wget -q -O xkcd-${nn}.json http://xkcd.com/$nn/info.0.json; tt="$(sed 's/.*"title": "\([^"]\+\)",.*/\1/' ...
    fpunktk · 2012-01-06 20:26:11 0

  • -1
    vgdisplay -v 2>/dev/null | grep "^ LV Name" | while read A B LVDEV; do echo $LVDEV; done
    f4m8 · 2011-12-09 14:57:50 1

  • 2
    while read l; do echo -e "$RANDOM\t$l"; done | sort -n | cut -f 2
    unixmonkey28183 · 2011-12-09 01:02:27 1
  • Schematics: command [options] [paste your variable here] parameter command [options] [paste entire column of variables here] parameter ... (hard-code command "c" and parameter "e" according to your wishes: in example shown command = "cp -a" and parameter = "~") Features: - Quick exchange only variable part of a long command line - Make variable part to be an entire column of data (i.e. file list) - Full control while processing every single item Hints: Paste column of data from anywhere. I.e. utilize the Block Select Mode to drag, select and copy columns (In KDE Konsole with Ctrl+Alt pressed, or only Ctrl pressed in GNOME Terminal respectively). Disadvantages: You can paste only one single variable in a row. If there are more space separated variables in a row only first one will be processed, but you can arrange your variables in a column instead. To transpose rows to columns or vice versa look at Linux manual pages for 'cut' and 'paste'. TODO: - add edit mode to vary command "c" and parameter "e" on the fly - add one edit mode more to handle every list item different - add y/n/a (=All) instead of only y(=default)/n to allowed answers Disclaimer: The code is not optimized, only the basic idea is presented here. It's up to you to shorten code or extend the functionality. Show Sample Output


    -1
    c="cp -a";e="~";echo -e "\npaste\n";i=0;k="1"; while [[ "$k" != "" ]]; do read -a k;r[i]=$k;((i++));done;i=0;while :;do t=${r[i]};[ "$t" == "" ] && break; g=$(echo $c ${r[i]} $e);echo -e $g "\ny/n?";read y;[ "$y" != "n" ] && eval $g;((i++));done
    knoppix5 · 2011-12-04 12:45:44 0
  • Do not use JPEG, GIF, or any other 'lossy' image encoding with Encryption


    0
    read -s PASS; echo $PASS | convert sensitive.jpg -encipher - -depth 8 png24:hidden.png
    kev · 2011-11-25 18:15:23 5
  • Why remember? Generate! Up to 48 chars, works on any unix-like system (NB: BSD use md5 instead of md5sum) Show Sample Output


    24
    read -s pass; echo $pass | md5sum | base64 | cut -c -16
    bugmenot · 2011-11-24 20:23:47 9
  • Exit with empty line


    -7
    read c; while [ -n "$c" ]; do clear; echo -e "$c = "$(echo "$c" |bc -l)"\n"; read c; done
    mrttlemonde · 2011-11-13 10:28:40 2
  • Handle any bad named file which contains ",',\n,\b,\t,` etc Store the file name as null character separated list find . -print0 >name.lst and retrieve it using read -r -d "" Eg: find . -print0 >name.lst; cat name.lst| while IFS="" read -r -d "" file; do ls -l "$file"; done Show Sample Output


    1
    read -d ""
    totti · 2011-10-25 18:44:11 0
  • Consider the following simple situation [ reading something using while and read ] [See script 1 in sample output] --------------------------------------------------- The variable var is assigned with "nullll" at first. Inside the while loop [piped while] it is assigned with "whillleeee". [Onlly 2 assignments stmts]. Outside the loop the last assigned value for "var" [and no variable] inside the while can't be accessed [Due to pipe, var is executed in a sub shell]. In these type of situation variables can be accessed by modifying as follows. [See script 2 in sample output] ___________________________ Vary helpful when reading a set of items, say file names, stored on a file [or variable] to an array an use it later. Is there any other way 2 access variables inside and outside the loop ?? Show Sample Output


    -5
    while read line; do echo $line; done <<< "$var"
    totti · 2011-09-22 16:53:32 0

  • -1
    find . -printf "%T@ %p\n" | sed -e 1d | while read ts fn; do ts=${ts%.*}; if [ $ts -ge ${gts:-0} ]; then gts=$ts; echo `date -d @$gts` $fn; fi; done
    bandie91 · 2011-09-13 08:00:27 0
  • I find it useless but definitely simpler than #9230 Show Sample Output


    8
    read -ra words <<< "<sentence>" && echo "${words[@]^}"
    RanyAlbeg · 2011-09-10 02:46:42 2
  • Can be used for command line parameters too. If you have a more complicated way of entering values (validation, GUI, ...), then write a function i.e. EnterValue() that echoes the value and then you can write: param=${param:-$(EnterValue)}


    8
    param=${param:-$(read -p "Enter parameter: "; echo "$REPLY")}
    frans · 2011-09-08 20:48:31 0
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