IND$FILE

[Jim Brain via cctalk]

I know it's a minor nit, but as someone who has used IND$FILE on OS/390 
(zOS), I always wondered why it was called IND$FILE. Wikipedia has just 
a stub:

https://en.wikipedia.org/wiki/IND$FILE
FILE I tend to understand, but I was never very knowledgeable of MVS, so 
I'm not sure where IND comes from.

Jim