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 7
  • 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 3
  • 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 9
  • 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 8
  • 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 4
  • 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 5
  • 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 3
  • 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 3
  • 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 9
  • 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 10

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Instant mirror from your laptop + webcam

Put split files back together, without a for loop
After splitting a file, put them all back together a lot faster then doing $cat file1 file2 file3 file4 file5 > mainfile or $for i in {0..5}; do cat file$i > mainfile; done When splitting, be sure to do split -d for getting numbers instead of letters

write the output of a command to /var/log/user.log... each line will contain $USER, making this easy to grep for.
This command is useful if you want to copy the output of a series of commands to a file, for example if you want to pastebin the output from 'uname -a', 'lspci -vvv' and 'lsmod' for video driver trouble-shooting on your favorite Linux forum. 'log' takes all the following arguments as a command to execute, with STDOUT sent to /var/log/user.log. The command is echoed to the log before it is executed. The advantages of using logger (as opposed to appending output from commands to a file) are 1) commands are always appended to the logs... you don't have to worry about clobbering your log file accidentally by using '>' rather than '>>' 2) logs are automatically cleaned up by logrotate. The following functions allow you to mark the start and end of a section of /var/log/user.log. $ startlog() { export LOGMARK=$(date +%Y.%m.%d_%H:%M:%S); echo "$LOGMARK.START" | logger -t $USER; } then $ endlog() { echo "$LOGMARK.END" | logger -t $USER; } printlog will print all lines between $LOGMARK.START and $LOGMARK.END, removing everything that is prepended to each line by logger. $ printlog() { sudo sed -n -e "/$LOGMARK.START/,/$LOGMARK.END/p" /var/log/user.log| sed "s/.*$USER: //"; } The following command should dump just about all the information that you could possibly want about your linux configuration into the clipboard. $ startlog; for cmd in 'uname -a' 'cat /etc/issue' 'dmesg' 'lsusb' 'lspci' 'sudo lshw' 'lsmod'; do log $cmd; done; endlog; printlog | xsel --clipboard This is ready for a trip to http://pastebin.com/, and you don't have to worry about leaving temporary files lying around cluttering up $HOME. Caveats: I'm sure that startlog, endlog, and printlog could use some cleanup and error checking... there are unchecked dependencies between printlog and endlog, as well as between endlog and startlog. It might be useful for 'log' to send stderr to logger as well.

Poor man's nmap for a class C network from rfc1918
What do you do when nmap is not available and you want to see the hosts responding to an icmp echo request ? This one-liner will print all hosts responding with their ipv4 address.

get colorful side-by-side diffs of files in svn with vim
This will diff your local version of the file with the latest version in svn. I put this in a shell function like so: $svd() { vimdiff

GRUB2: set Super Mario as startup tune
I'll let Slayer handle that. Raining Blood for your pleasure.

Keep track of diff progress
You're running a program that reads LOTS of files and takes a long time. But it doesn't tell you about its progress. First, run a command in the background, e.g. $ find /usr/share/doc -type f -exec cat {} + > output_file.txt Then run the watch command. "watch -d" highlights the changes as they happen In bash: $! is the process id (pid) of the last command run in the background. You can change this to $(pidof my_command) to watch something in particular.

df output, sorted by Use% and correctly maintaining header row
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!

Extract public key from private
This will extract the public key that is stored in the private key using openssl.

Annotate tail -f with timestamps

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