in reply to 2 basic questions
Just playing, may not work in your character set:
perl -le "while(1){$a=$a?$a:ord'a';print chr$a;$a=++$a%ord'{';sleep 1} +"
This probably will though
perl -le "$_='x';while(1){s/aa/a/;print$_++;sleep 1}"
Cheers,
R.
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