Bug in rand() and srand()

[jpk at ur-univax.UUCP]

The same bug in rand() appears on the VMS C compiler (VAX-11 C)!

When I reported it to DEC, they had never discovered it.

I happened to find it because I was using rand() to generate
a random noise graphic, and discovered an awful lot of pattern
in a supposedly randomly generated display.  What happened was
I made two successive calls to rand() to generate an x and y
coordinate, so all my x's fell on odd spaces, all my y's on
even.  Half the points were never chosen on my screen, and
a very regular half!

The fix was to call MTH$RANDOM on VMS, and random() on unix.
The moral:  compatible function libraries don't support compatible
systems when the original version was bugged!  Instead, they
support bugged, but compatible, code.  Equally wrong on VMS
or unix!!!

					-- Jon Krueger