UNIX source code errors detected by new C compiler

[Guy Harris]

The trouble is that multiple global definitions aren't seen by the compiler
(unless you do something strange) but by the linker.  The UNIX 5.0 (System V)
linker DOES forbid them, I believe.  (BTW, the "=+" operators and
initializations without "=" are no longer supported by the 5.0 C compiler.)
I have gotten into the habit of using "extern" in all declarations in include
files and putting the definition of the global in only one source file.

	Guy Harris
	{seismo,mcnc,we13,brl-bmd,allegra}!rlgvax!guy