Re: #ifdef __cplusplus

Richard Heathfield wrote:
> Ian Collins said:
> 
>> Richard Heathfield wrote:
>>> mattia said:
>>>
>>>> I've see in some code:
>>>>
>>>> #ifdef __cplusplus
>>>>  extern "C"
>>>>  { 
>>>> #endif
>>>>
>>>> what does it mean?
>>> It means that someone hasn't decided which language they're writing
in.
>> Utter nonsense.
> 
> Hmmm.
> 
>> So are you saying the authours of all my system headers
>> didn't know which language they're writing in?
> 
> Are /you/ saying they've introduced illegal syntax into C translation 
> units, protected only by a #ifdef of a symbol for which the Standard 
> defines no meaning and on which C90 imposes no special conditions?
> 
In all but one header, no.  They are simply informing C++ compilers that
the C standard library function have C linkage.  No illegal syntax there.

The exception is in <string.h>, where C++ adds overloads for the broken
C library functions (strchr() for example) that return a char* to a
const char* argument.

> If so, then yes, I'd say they didn't know which language they were
writing 
> in.
> 
If so, they most certainly did.

-- 
Ian Collins.