PATCH: Adhere to section 17.4.1.2 clause 5 of ISO 14882:1998

[Gabriel Dos Reis]

Loren James Rittle <rittle@latour.rsch.comm.mot.com> writes:

[...]

| Assuming a liberal reading of this section, errno should be provided
| as a macro even if the C implementation is something other than a
| function or a macro (i.e. it is a global variable with external
| linkage)...

There has been a discussion to that effect on comp.std.c++ recently,
and Steve Clamage's reading 
	
	Message-ID: <3AB935DC.325E6AAF@sun.com>

is that errno has an external linkage, thus it cannot be a macro
name. 

-- Gaby