What is the origin of the prepended underscore?

[Chris Torek]

>Why is an underscore commonly prepended to symbols generated by most C
>compilers?

The answer is so that variables like "r3" don't conflict with
registers like "r3", and so forth.  However, while it is no longer
important now that we have flexnames, I would like to take this
opportunity to wonder why the _ was not *ap*pended to external
symbols, giving one eight significant characters between .o files
instead of seven.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 4251)
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