exists()

[Fairlight]

The honourable and venerable Kenneth Brody spoke thus:
> 
> What O/S are you on?  On my Linux box, error 13 is "permission denied".

Linux is POSIX-compliant.  Assuming errno numbers and definitions are
standardised within POSIX, t's going to be the same on any POSIX-based
unixen, and probably most of them that don't even claim to be.  Almost
certainly it should be the same on any *nix on which fP is supported.

mark->
-- 
Most people think the defining traits of human beings are intelligence,
speech, writing, or creativity.  The sad reality is that the most singular
defining quality of humanity is cruelty.  No other species appears to be so
able and willing to inflict pain on its brethren for no logical reason.