rand48(3) not drand48(3) to align with the actual man page and Xr
entries.
Move guts of setbuf.3 into setvbuf.3 to make it clear which one
should be used in new code.
Warn people to use arc4random() in DESCRIPTION so they see it using
the same text from random.3.
Don't describe random() as "better".
Remove the bug about rand() being faster.
Add a bug about historical implementations seeding very poorly.
rand() is a pseudo-random number generator
C99 says setvbuf() returns non-zero, not EOF.  Also, POSIX documents
that it returns an error for invalid mode which matches our behavior.
OK jmc@ deraadt@
zap trailing whitespace;
macro cleanup; from kaspars at bankovskis dot net