Commands by fpunktk (10)

  • Print one . instead of each line

    this version only uses shell builtins


    1
    alias ...='while read line; do echo -n "."; done && echo ""'
    fpunktk · 2014-03-17 17:34:19 0
  • a tail function for automatic smart output

    tail() { thbin="/usr/bin/tail"; if [ "${1:0:1}" != "-" ]; then fc=$(($#==0?1:$#)); lpf="$((($LINES - 3 - 2 * $fc) / $fc))"; lpf="$(($lpf<1?2:$lpf))"; [ $fc -eq 1 ] && $thbin -n $lpf "$@" | /usr/bin/fold -w $COLUMNS | $thbin -n $lpf || $thbin -n $lpf "$@"; else $thbin "$@"; fi; unset lpf fc thbin; } This is a function that implements an improved version of tail. It tries to limit the number of lines so that the screen is filled completely. It works with pipes, single and multiple files. If you add different options to tail, they will overwrite the settings from the function. It doesn't work very well when too many files (with wrapped lines) are specified. Its optimised for my three-line prompt. It also works for head. Just s/tail/head/g Don't set 'thbin="tail"', this might lead to a forkbomb.


    -1
    tail() { thbin="/usr/bin/tail"; if [ "${1:0:1}" != "-" ]; then fc=$(($#==0?1:$#)); lpf="$((($LINES - 3 - 2 * $fc) / $fc))"; lpf="$(($lpf<1?2:$lpf))"; [ $fc -eq 1 ] && $thbin -n $lpf "$@" | /usr/bin/fold -w $COLUMNS | $thbin -n $lpf || $thbin -n $lpf...
    fpunktk · 2012-03-23 19:00:30 0
  • diff the outputs of two programs

    I've been looking for this for a long time. Does anybody know how to do this in dash (POSIX shell)? An alternative version might be: exiftool img_1.jpg | diff - <(exiftool img_2.jpg)


    9
    diff <(exiftool img_1.jpg) <(exiftool img_2.jpg)
    fpunktk · 2012-01-30 22:01:17 1
  • add title and alt-text to your collection of xkcd comics

    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
  • Command line calculator

    This is an "argument calculator" funktion. The precision is set to 4 and you can use dot (.) or comma (,) as decimal mark (which is great for german users with a comma on the numpad).


    -1
    calc() { echo "scale=4; ${*//,/.}" | bc -l; }
    fpunktk · 2011-10-24 19:58:20 0
  • Command line calculator

    This opens a python command line. You can use math and random and float-division is enabled (without appending .0 to integers). I just don't know how to specify a standard precision.


    1
    python -ic "from __future__ import division; from math import *; from random import *"
    fpunktk · 2011-10-24 19:47:27 1
  • get the oldest file in a directory

    reverse the sorting of ls to get the newest file: ls -1tr --group-directories-first /path/to/dir/ | tail -n 1 Problems: If there are no files in the directory you will get a directory or nothing.


    1
    ls -1t --group-directories-first /path/to/dir/ | tail -n 1
    fpunktk · 2010-12-02 12:25:16 0
  • translate with google, get all translations

    the google-api gives you only one translation which is sometimes insufficent. this function gives you all translations, so you can choose which one fits best.


    1
    translate() { echo $1: $(wget -q -O - 'http://www.google.de/dictionary?source=translation&q='$1'&langpair=en|de' | grep '^<span class="dct-tt">.*</span>$' | sed 's!<span class="dct-tt">\(.*\)</span>!\1, !'); }
    fpunktk · 2010-09-02 00:08:06 0
  • bash-quine

    this command prints itself out. it doesn't need to be stored in a file and it isn't as easy as echo $BASH_COMMAND for information on quines see http://en.wikipedia.org/wiki/Quine_(computing)


    4
    s='s=\47%s\47; printf "$s" "$s"'; printf "$s" "$s"
    fpunktk · 2010-05-09 16:52:58 0
  • delete duplicate lines from a file and keep the order of the other lines

    i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines. the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.


    4
    cat -n <file> | sort -k 2 | uniq -f 1 | sort -n | cut -f 2-
    fpunktk · 2010-01-21 18:55:58 3

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GZip all files in a directory separately

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

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" }

See how many more processes are allowed, awesome!
There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100. $ OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 \( -user $USER -o -group $GROUPNAME \) -type d|wc -l`) / 2 )) This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript). An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command. $ find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p' I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this: $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this. $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' If you were building a process-killer (very common for cheap hosting) this would also be handy. Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.

Get My Public IP Address

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

List the size (in human readable form) of all sub folders from the current location
Tested on MacOS and GNU/Linux. It works in dirs containing files starting with '-'. It runs 'du' only once. It sorts according to size. It treats 1K=1000 (and not 1024)

Sort a character string
Sorts a character string, using common shell commands.

list files recursively by size

Run CPU benchmark from command line
Run CPU benchmark from command line

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