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

Matrix Style

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

7
By: zzambia
2009-07-02 07:10:33

10 Alternatives + Submit Alt


  • 64
    tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"
    allinurl · 2009-06-30 17:23:49 7
  • I like the fact the Patola's version uses only ones and zeros, but I also like the sparse output of the other versions. This one combines both of those features and eliminates some unnecessary cruft. You can vary the sparseness by changing "$(($RANDOM % 5))" to another number. The number in this term "$(($RANDOM % 4))" controls how frequently the numbers are output bold.


    21
    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
    dennisw · 2009-09-27 15:30:38 2

  • 6
    COL=$(( $(tput cols) / 2 )); clear; tput setaf 2; while :; do tput cup $((RANDOM%COL)) $((RANDOM%COL)); printf "%$((RANDOM%COL))s" $((RANDOM%2)); done
    sputnick · 2009-12-15 02:48:28 2
  • 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.


    4
    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
    psykotron · 2009-12-19 19:05:04 1
  • 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.


    2
    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;
    Patola · 2009-07-10 04:20:43 2

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 "[^ ]"
Dereckson · 277 weeks and 5 days ago

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