Filesystems and case-insensitivity

I believe there are two control characters RS1 and RS2? Basically standing for "Repeat String"? Which were used on a system I worked on, and actually were a damn good fix for "how many characters does a tab stand for?". So most lines in my FORTRAN source code would have been physically stored on disk as "<RS1><6>code..."

And if you had a lot of spaces it saved a fair few bytes over tab-encoding, plus being completely unambiguous.

Cheers,
Wol