Question about PERL_NO_DEV_RANDOM

As part of my clean up for Perl_seed() I see we have this weird define 
PERL_NO_DEV_RANDOM. Grepping the source code the ONLY place I see that 
defined is in *dosish.h* which appears to be a config file for building 
Perl for old DOS systems. Do we use *dosish.h *for any modern supported 
systems?

The only thing this define does is tell Perl_seed() skip trying to read 
from */dev/urandom*. Since this is for older DOS systems which I don't 
think we support (?) can this check be removed? Without that define in 
place, even on DOS systems, the code will fail to read from 
*/dev/urandom* (because it doesn't exist) and fail back to hashing state 
variables instead.

Nothing would change in the codepath, it would just make the code 
cleaner and more readable by having one less obscure define.

-- Scottchiefbaker