Commands by rodolfoap (16)

  • The Piano Phase piece, by Steve Reich is a minimalist composition which is played on two pianos played at slightly different tempos, a task that's very difficult to accomplish by human players. The auditive effects produced by the cell displacement produce beautiful patterns. See https://en.wikipedia.org/wiki/Piano_Phase . My rendered version: https://ydor.org/SteveReich/piano_phase.mp3 Requires sox to be installed on the system. There are multiple videos on youtube showing different approaches and experiences to this interpretation. There is also a synthesized version. Even if Bash can behave as a powerful pianist, a simple threaded version leaves full room to several time glitches and even negative displacements, the same issues that human pianists experience when playing the piece. The older the computer, the better the chaos added to the result due to the CPU load. Apparently that's the reason Steve Reich composes pieces such as this. Without further ado, please give a warm welcome to the Bash minimalist player on synthesized two-threaded pianos. Please turn off your cellphones.


    1
    phase() { while :; do for n in E4 F#4 B4 C#5 D5 F#4 E4 C#5 B4 F#4 D5 C#5; do /usr/bin/play -qn synth $1 pluck $n; done; echo -n "[$1]"; done; }; phase 0.13 & phase 0.131 &
    rodolfoap · 2017-06-14 20:29:26 14
  • This function will encrypt a bash script and will only execute it after providing the passphrase. Requires mcrypt to be installed on the system. Show Sample Output


    1
    scrypt(){ [ -n "$1" ]&&{ echo '. <(echo "$(tail -n+2 $0|base64 -d|mcrypt -dq)"); exit;'>$1.scrypt;cat $1|mcrypt|base64 >>$1.scrypt;chmod +x $1.scrypt;};}
    rodolfoap · 2017-06-14 16:27:20 12
  • Lost your luks passphrase? You can always bruteforce from the command line. See the sample output, a simple command using a dictionary. Show Sample Output


    0
    cat dictionary.txt|while read a; do echo $a|cryptsetup luksOpen /dev/sda5 sda5 $a && echo KEY FOUND: $a; done
    rodolfoap · 2014-04-16 18:49:53 6
  • Lost your luks passphrase? You can always bruteforce from the command line. See the sample output, a simple command for the "pass" word, using combinations of upper/lowercase or number replacement. The generated combinations are: for a in {p,P}{a,A,4}{s,S,5}{s,S,5}; do echo $a; done pass pasS pas5 paSs paSS paS5 ... Show Sample Output


    1
    for a in {p,P}{a,A,4}{s,S,5}{s,S,5}; do echo $a|cryptsetup luksOpen /dev/sda5 $a && echo KEY FOUND: $a; done
    rodolfoap · 2014-04-16 18:41:50 3
  • Reads n lines from stdin and puts the contents in a variable. Yes, I know the read command and its options, but find this logical even for one line. Show Sample Output


    -2
    VAR=$(head -5)
    rodolfoap · 2014-04-05 13:45:18 3
  • (Please see sample output for usage) Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.: myscript --> myscript.crypt You can execute myscript.crypt only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Sorry for the chmod on parentheses, I dont like "-" at the end. Thanks flatcap for the subshell abbreviation to /dev/null Show Sample Output


    6
    read -p 'Script: ' S && C=$S.crypt H='eval "$((dd if=$0 bs=1 skip=//|gpg -d)2>/dev/null)"; exit;' && gpg -c<$S|cat >$C <(echo $H|sed s://:$(echo "$H"|wc -c):) - <(chmod +x $C)
    rodolfoap · 2013-03-10 08:59:45 11
  • (Please see sample output for usage) script.bash is your script, which will be crypted to script.secure script.bash --> script.secure You can execute script.secure only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Show Sample Output


    5
    echo "eval \"\$(dd if=\$0 bs=1 skip=XX 2>/dev/null|gpg -d 2>/dev/null)\"; exit" > script.secure; sed -i s:XX:$(stat -c%s script.secure): script.secure; gpg -c < script.bash >> script.secure; chmod +x script.secure
    rodolfoap · 2013-03-09 11:16:48 9
  • This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it. USAGE: SEE SAMPLE OUTPUT The file is composed of three parts: a) The legible script (about 242 bytes) b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242) c) The actual filesystem Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option. PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :) It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file. The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables. Show Sample Output


    6
    dd if=/dev/zero of=T bs=1024 count=10240;mkfs.ext3 -q T;E=$(echo 'read O;mount -o loop,offset=$O F /mnt;'|base64|tr -d '\n');echo "E=\$(echo $E|base64 -d);eval \$E;exit;">F;cat <(dd if=/dev/zero bs=$(echo 9191-$(stat -c%s F)|bc) count=1) <(cat T;rm T)>>F
    rodolfoap · 2013-01-31 01:38:30 11
  • Would create a file with a meaningful title. Dedicated to John Cons, who is annoying us users. Merry Christmas!!! Show Sample Output


    7
    alias Z=base64&&Z=dG91Y2ggUExFQVNFX1NUT1BfQU5OT1lJTkdfQ09NTUFORExJTkVGVV9VU0VSUwo=&&$(echo $Z|Z -d)
    rodolfoap · 2010-12-24 14:29:19 16
  • Im' not interested in images, but that's how I would do it.


    0
    curl -s http://boards.4chan.org/wg/|sed -r 's/.*href="([^"]*).*/\1\n/g'|grep images|xargs wget
    rodolfoap · 2010-12-12 06:32:19 2
  • Shows a zenity progressbar for each file in a script, see the samble output. Works with any number, less, equal or greater than 100. x is not initially defined. If used twice in the script, set it: x=0 (for FILE in $@; do echo $[100*++x/$#]; command... "$FILE"; done)|zenity --progress --auto-close Show Sample Output


    0
    (for FILE in $@; do echo $[100*++x/$#]; command-for-each-parameter; done)|zenity --progress --auto-close
    rodolfoap · 2010-10-05 10:07:04 4
  • Simple alternative to the previous submitted one


    8
    pdftk in.pdf burst
    rodolfoap · 2010-02-10 13:31:36 9
  • Better -and faster- using bash printf. Show Sample Output


    -2
    printf "%50s\n"|tr ' ' -
    rodolfoap · 2010-01-07 08:49:46 5
  • Felt like I need to win the lottery, and wrote this command so I train and develop my guessing abilities. Show Sample Output


    13
    A=1;B=100;X=0;C=0;N=$[$RANDOM%$B+1];until [ $X -eq $N ];do read -p "N between $A and $B. Guess? " X;C=$(($C+1));A=$(($X<$N?$X:$A));B=$(($X>$N?$X:$B));done;echo "Took you $C tries, Einstein";
    rodolfoap · 2009-12-16 13:24:23 86
  • Today I needed to choose an icon for an app. My simpler way: put all of /usr/share/icons in myicons folder and brows'em with nautilus. Then rm -r 'ed the entire dir. Show Sample Output


    2
    mkdir myicons && find /usr/share/icons/ -type f | xargs cp -t myicons
    rodolfoap · 2009-12-09 17:43:28 6
  • find makes it easier, filtering . and .. maxdepth could be removed, finding entries recursively. Removing mindepth causes . to appear Show Sample Output


    1
    find -mindepth 1 -maxdepth 1 -name .\*
    rodolfoap · 2009-11-24 22:18:33 4

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Locate config files of the program
Locate config files of the program. May not be used for interactive programs like vim.

Share a screen session

Copy an element from the previous command
You can specify a range via '-'.

Get IP address from domain

Add page numbers to a PDF
Put this code in a bash script. The script expects the PDF file as its only parameter. It will add a header to the PDF containing the page numbers and output it to a file with the suffix "-header.pdf" Requires enscript, ps2pdf and pdftk.

convert markdown to PDF
This is the one-line version of this htmldoc + markdown combo to convert markdown formatted text to PDF files to distribute to your non-savvy project managers. http://scottnesbitt.net/ubuntublog/?p=114

Get a free shell account on a community server
Bash process substitution which curls the website 'hashbang.sh' and executes the shell script embedded in the page. This is obviously not the most secure way to run something like this, and we will scold you if you try. The smarter way would be: Download locally over SSL > curl https://hashbang.sh >> hashbang.sh Verify integrty with GPG (If available) > gpg --recv-keys 0xD2C4C74D8FAA96F5 > gpg --verify hashbang.sh Inspect source code > less hashbang.sh Run > chmod +x hashbang.sh > ./hashbang.sh

Retrieve "last modified" timestamp of web resource in UTC seconds
This command line assumes that "${url}" is the URL of the web resource. It can be useful to check the "freshness" of a download URL before a GET request.

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"

Undo commit in Mercurial


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