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Matrix Style

Terminal - Matrix Style
LC_ALL=C tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"
2009-07-02 07:10:33
User: zzambia
Functions: dd grep tr
6
Matrix Style

Solves "tr" issues with non C-locales under BSD-like systems (like OS X)

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"
2009-06-30 17:23:49
User: allinurl
Functions: dd grep tr
Tags: color
61
echo -e "\e[32m"; while :; do for i in {1..16}; do r="$(($RANDOM % 2))"; if [[ $(($RANDOM % 5)) == 1 ]]; then if [[ $(($RANDOM % 4)) == 1 ]]; then v+="\e[1m $r "; else v+="\e[2m $r "; fi; else v+=" "; fi; done; echo -e "$v"; v=""; done
2009-09-27 15:30:38
User: dennisw
Functions: echo
Tags: color
18

I like the fact the Patola's version uses only ones and zeros, but I also like the sparse output of the other versions. This one combines both of those features and eliminates some unnecessary cruft.

You can vary the sparseness by changing "$(($RANDOM % 5))" to another number. The number in this term "$(($RANDOM % 4))" controls how frequently the numbers are output bold.

COL=$(( $(tput cols) / 2 )); clear; tput setaf 2; while :; do tput cup $((RANDOM%COL)) $((RANDOM%COL)); printf "%$((RANDOM%COL))s" $((RANDOM%2)); done
echo -e "\e[31m"; while $t; do for i in `seq 1 30`;do r="$[($RANDOM % 2)]";h="$[($RANDOM % 4)]";if [ $h -eq 1 ]; then v="\e[1m $r";else v="\e[2m $r";fi;v2="$v2 $v";done;echo -e $v2;v2="";done;
2009-07-10 04:20:43
User: Patola
Functions: echo
Tags: color
3

It's the same command as submitted, but first with a command to make all characters green. It's the only way it looked "matrix-like" on my gnome-terminal.

echo -ne "\e[32m" ; while true ; do echo -ne "\e[$(($RANDOM % 2 + 1))m" ; tr -c "[:print:]" " " < /dev/urandom | dd count=1 bs=50 2> /dev/null ; done
2009-12-19 19:05:04
User: psykotron
Functions: dd echo tr true
Tags: color
3

A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.

Know a better way?

If you can do better, submit your command here.

What others think

This command requires bash. Please don't use BSD-like system if your command isn't shell-agnostic.

On tcsh, $COLUMNS isn't defined.

[ Bash is now the Mac OS X default shell ]

According http://support.apple.com/kb/TA27005:

The default shell (or command-line interface) used in Mac OS X 10.0 through 10.2.8 is tcsh (with 10.3 and 10.4 it's bash). With Mac OS X 10.2 or later, other interactive shells are included, such as bash and zsh.

[ How to make this work on every BSD system ? ]

sh

LC_ALL=C tr -c "[:digit:]" " " < /dev/urandom | dd cbs=80 conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"

Comment by Dereckson 79 weeks and 2 days ago

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