Scrolling plan file

Question

How do I create a scrolling plan file? I read about their existence here http://www.catb.org/jargon/html/P/plan-file.html, but it doesn't explain how to actually make them.

Answer 1

There's a compiler called asp for creating such files available here.

The problem with these now is that terminals are just too darn fast. This technique was used with slooow serial or dial-up connections. The techniques relies on sending a really large file consisting of text, carriage returns and sometimes newlines.

You can enjoy these files today by introducing a timing loop. Perhaps the easiest way is to use pv.

pv -q -L 1200 .plan

Answer 2

It's quite simple really - a file filled with subsequent frames of a single line animation separated with a carriage return (not line feed) so each line overwrites the line before.

E.g., (\r is carriage return)

......<\r.....<.\r....<..\r...<...\r..<....\r.<.....\r<......\r

would animate an arrow moving left through some dots. Delays can be created by having either multiple carriage returns, or repeating the same frame many times.