Commands using read (315)

  • POSIX requires this "string truncating" functionality. might as well use it, at least for very small tasks where invoking sed and using RE is overkill.


    1
    se(){ while read a;do [ "$a" != "${a#*$@*}" ]&&echo $a;done ;} # usage: se pattern # use in place of sed /pat/!d where RE are overkill
    argv · 2011-04-06 03:37:40 2
  • This shows a list of channels from seeon.tv website to watch shows and movies


    -1
    lynx --dump http://www.seeon.tv/channels| grep "/channels"|awk '{print $2}'|sort -u|while read links; do lynx --dump "$links"|awk '/view/ {print $2}'|sort -u; done
    Bonster · 2011-04-01 05:58:20 0
  • Show disk space info, grepping out the uninteresting ones beginning with ^none while we're at it. The main point of this submission is the way it maintains the header row with the command grouping, by removing it from the pipeline before it gets fed into the sort command. (I'm surprised sort doesn't have an option to skip a header row, actually..) It took me a while to work out how to do this, I thought of it as I was drifting off to sleep last night! Show Sample Output


    0
    df -h | grep -v ^none | ( read header ; echo "$header" ; sort -rn -k 5)
    purpleturtle · 2011-03-16 14:25:45 1
  • a simple interactive tool to convert Simplified Chinese (typed by pinyin) to Traditional Chinese Show Sample Output


    0
    echo "Simplied Chinese:"; while read -r line; do echo "Traditional Chinese:"; echo $line | iconv -f utf8 -t gb2312 | iconv -f gb2312 -t big5 | iconv -f big5 -t utf8; done
    dexterhu · 2011-03-11 12:26:25 9

  • -1
    fdupes -r -1 path | while read line; do j="0"; for file in ${line[*]}; do if [ "$j" == "0" ]; then j="1"; else sudo ln -f ${line// .*/} $file; fi; done; done
    piti · 2011-03-07 11:16:09 2
  • This is a simple bash function and a key binding that uses commandlinefu's simple and easy search API. It prompts for a search term, then it uses curl to search commandline fu, and highlights the search results with less.


    0
    function ds { echo -n "search : "; read ST; EST=`php -r "echo rawurlencode('$ST');"`; B64=`echo -n $ST| openssl enc -base64`; curl -s "http://www.commandlinefu.com/commands/matching/$EST/$B64/plaintext" | less -p "$ST"; } ; bind '"\C-k"':"\"ds\C-m\""
    cparker · 2011-02-20 23:46:16 0
  • Take a folder full of files and split it into smaller folders containing a maximum number of files. In this case, 100 files per directory. find creates the list of files xargs breaks up the list into groups of 100 for each group, create a directory and copy in the files Note: This command won't work if there is whitespace in the filenames (but then again, neither do the alternative commands :-)


    -1
    files -type f | xargs -n100 | while read l; do mkdir $((++f)); cp $l $f; done
    flatcap · 2011-02-15 23:15:16 1

  • 1
    $ right(){ l="$(cat -)"; s=$(echo -e "$l"| wc -L); echo "$l" | while read l;do j=$(((s-${#l})));echo "$(while ((j-->0)); do printf " ";done;)$l";done;}; ls --color=none / | right
    glaudiston · 2011-02-14 16:58:37 5
  • Center the output text in max line length of buffered output pipe; Show Sample Output


    0
    center(){ l="$(cat -)"; s=$(echo -e "$l"| wc -L); echo "$l" | while read l;do j=$(((s-${#l})/2));echo "$(while ((--j>0)); do printf " ";done;)$l";done;}; ls --color=none / | center
    glaudiston · 2011-02-14 16:50:35 2
  • Smaller Code Better Runtime


    0
    find files/ -type f | while read line; do if [ $((i++%100)) -eq 0 ]; then mkdir $((++folder)); fi; cp $line $folder/; done
    sraeder · 2011-02-13 00:25:48 0
  • just an alternative to #7818 Show Sample Output


    0
    exec 3<&0; ls -1N | while read a; do echo "Rename file: $a"; read -e -i "$a" -p "To: " b <&3 ; [ "$a" == "$b" ] || mv -vi "$a" "$b"; done
    forcefsck · 2011-02-08 21:21:39 0
  • i use this after ripping internet radio streams to number the files as they originally played (even though streamripper can do this with -q). to number other types of files, or all files, just change the *mp3. to rename directories only you could use ... ls -lt | grep ^d | cut -d ":" -f2 | cut -d " " -f2- | while read ... Show Sample Output


    0
    IFS=$'\n'; i=1; ls -lt *mp3 | cut -d ":" -f2 | cut -d " " -f2- | while read f; do mv "$f" $(echo "$i"."$f"); ((i++)); done
    m1cawber · 2011-01-22 00:21:12 3

  • -5
    echo -en "$USER@$HOSTNAME:${PWD##*/}> ";while read x;do echo $x>>/tmp/log.txt;echo $x|$0 2>&1;echo -en "$USER@$HOSTNAME:${PWD##*/}> ";done
    Nikon · 2011-01-17 20:53:28 0

  • 3
    bargs { while read i; do "$@" "$i"; done }
    wytten · 2011-01-06 19:25:43 1
  • can also be invoked as 'exipick -zi | exim -dM' if you do not need/want the delay between flushes.


    0
    exipick -zi | while read x ; do exim -dM "$x"; sleep 1;done
    alustenberg · 2011-01-04 20:17:30 0
  • No need for further filedes or substitution for splitting. Simply use read a b


    1
    grep -i "$*" /usr/lib/perl5/Unicode/CharName.pm | while read a b; do /usr/bin/printf "\u$a\tU+%s\t%s\n" "$b"; done
    ioggstream · 2011-01-04 11:30:16 2

  • 0
    $ find . -iname *.mp3 | while read line ; do ln -s "$line" $(echo -e "$line" | openssl md5).mp3 ; done ; mpg123 *.mp3
    yababay · 2011-01-02 20:54:37 0
  • [Update! Thanks to a tip from ioggstream, I've fixed both of the bugs mentioned below.] You, yes, 𝙔𝙊𝙐, can be the terror of the Internet! Why use normal, boring bullet points in your text, when you could use a ROTATED HEAVY BLACK HEART BULLET (❥)!? (Which would also be an awesome band name, by the way).  This script makes it easy to find unusual characters from the command line. You can then cut and paste them or, if you're using a GTK application, type Control+Shift+U followed by the code point number (e.g., 2765) and then a SPACE.  USAGE: Put this script in a file (I called mine "ugrep") and make it executable. Run it from the command line like so,  ugrep heart  The output will look like this,  ☙ U+2619 REVERSED ROTATED FLORAL HEART BULLET ♡ U+2661 WHITE HEART SUIT ♥ U+2665 BLACK HEART SUIT ❣ U+2763 HEAVY HEART EXCLAMATION MARK ORNAMENT ❤ U+2764 HEAVY BLACK HEART ❥ U+2765 ROTATED HEAVY BLACK HEART BULLET ❦ U+2766 FLORAL HEART ❧ U+2767 ROTATED FLORAL HEART BULLET ⺖ U+2E96 CJK RADICAL HEART ONE ⺗ U+2E97 CJK RADICAL HEART TWO ⼼ U+2F3C KANGXI RADICAL HEART  You can, of course, use regular expressions. For example, if you are looking for the "pi" symbol, you could do this:  ugrep '\bpi\b'  REQUIREMENTS: Although this is written in Bash, it assumes you have Perl installed because it greps through the Perl Unicode character name module (/usr/lib/perl5/Unicode/CharName.pm). Note that it would not have made more sense to write this in Perl, since the CharName.pm module doesn't actually include a subroutine for looking up a character based on the description. (Weird.)  BUGS: In order to fit this script in the commandlinefu limits, a couple bugs were added. ① Astral characters beyond the BMP (basic multilingual plane) are not displayed correctly, but see below. ② Perl code from the perl module being grepped is sometimes extraneously matched.  MISFEATURES: Bash's printf cannot, given a Unicode codepoint, print the resulting character to the terminal. GNU's coreutils printf (usually "/usr/bin/printf") can do so, but it is brokenly pedantic about how many hexadecimal digits follow the escape sequence and will actually die with an error if you give the wrong number. This is especially annoying since Unicode code points are usually variable length with implied leading zeros. The CharNames.pm file represents BMP characters as 4 hexits, but astral characters as 5. In the actual version of this script that I use, I've kludged around this misfeature by zero-padding to 8 hexits like so,  /usr/bin/printf "\U$(printf "%08x" 0x$hex)"  TIP 1: The author recommends "xsel" for command line cut-and-paste. For example,  ugrep biohazard | xsel  TIP 2: In Emacs, instead of running this command in a subshell, you can type Unicode code points directly by pressing Control-Q first, but you'll likely want to change the default input from octal to hexadecimal. (setq read-quoted-char-radix 16).  TIP 3: Of course, if you're using X, and you want to type one of the more common unusual characters, it's easiest of all to do it with your Compose (aka Multi) key. For example, hitting [Compose] <3 types ♥. Show Sample Output


    12
    egrep -i "^[0-9a-f]{4,} .*$*" $(locate CharName.pm) | while read h d; do /usr/bin/printf "\U$(printf "%08x" 0x$h)\tU+%s\t%s\n" $h "$d"; done
    hackerb9 · 2010-12-31 16:47:59 5
  • in case you run some command in CLI and would like to take read strerr little bit better, you can use the following command. It's also possible to grep it if necessary....


    19
    mycommand 2> >(while read line; do echo -e "\e[01;31m$line\e[0m"; done)
    confiq · 2010-12-30 21:42:42 10
  • To learn more about Google Ngram Viewer: http://ngrams.googlelabs.com/info


    1
    wget -qO - http://ngrams.googlelabs.com/datasets | grep -E href='(.+\.zip)' | sed -r "s/.*href='(.+\.zip)'.*/\1/" | uniq | while read line; do `wget $line`; done
    sexyprout · 2010-12-20 17:46:04 0
  • make, find and a lot of other programs can take a lot of time. And can do not. Supppose you write a long, complicated command and wonder if it will be done in 3 seconds or 20 minutes. Just add "R" (without quotes) suffix to it and you can do other things: zsh will inform you when you can see the results. You can replace zenity with other X Window dialogs program.


    1
    alias -g R=' &; jobs | tail -1 | read A0 A1 A2 cmd; echo "running $cmd"; fg "$cmd"; zenity --info --text "$cmd done"; unset A0 A1 A2 cmd'
    pipeliner · 2010-12-13 17:44:36 0

  • 10
    read -a ARR <<<'world domination now!'; echo ${ARR[2]};
    unefunge · 2010-12-03 16:27:03 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 1
  • This command finds all of the functions defined in any shell script you specify including .bashrc


    0
    functions(){ read -p "File name> "; sort -d $REPLY | grep "(){" | sed -e 's/(){//g' | less; }
    LinuxMan · 2010-12-01 18:49:48 0
  • cryptic version Show Sample Output


    2
    read -a A <<<"8 9 5 10 6 0 3 11 7 4";B='.*.**..*....***';for C in $(date +"%H%M"|fold -w1);do echo "${B:${A[C]}:4}";done
    unefunge · 2010-11-26 11:29:23 2
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