[Info-vax] callable BACKUP example

[Galen]

> This source code incorporation happens ~everywhere. I'd expect there 
> are OpenVMS source code examples that have found their way back into 
> OpenVMS itself. And elsewhere. 

Probably some similar process resulted in what I recount below.

I recall from a long-ago DECUS symposium (probably in an RSX "Magic Session") a DEC developer mentioning that there were scattered around the RSX sources (including libraries and utilities) redundant instances of the RAD50<->ASCII conversion code. ("Redundant" here meaning pointless. I can at least conceive of reasons why one component of the system might not be able to access the code instance in some other component.)

A wise guy in the audience (there were plenty of them in typical RSX Magic Sessions) replied, "That's so that if one copy of the code breaks, callers of the other non-broken copies won't be affected." I suppose an undetected memory error could lead to that... :-)