version and debug statements

[Sean Kelly]

Brad Roberts wrote:
> On Thu, 11 May 2006, Walter Bright wrote:
> 
>> Sean Kelly wrote:
>>> For what it's worth, I think it would be useful for the 'Posix' version to
>>> be added, so any system supporting POSIX would have version 'Posix'
>>> automatically specified in addition to any OS version identifier.  This
>>> would be similar to how Windows platforms also have either 'Win32' or
>>> 'Win64' defined.  While a good bit of POSIX declarations are indeed
>>> implementation dependent, an equally large amount are not, and I believe it
>>> would be useful for a version identifier to reflect this.
>> Having large parts of Posix be implementation dependent kinda shoots the whole
>> idea of a standard in the foot.
> 
> I feel the need to cry foul here, a little.  Which parts are 
> implementation defined?  How widely used are those parts?  In my 
> experience, the vast majority of the parts that are used with any major 
> frequency are identical between the various posix compliant operating 
> systems.

For what it's worth, when I refer to Posix I mean the spec defined here:

http://www.opengroup.org/onlinepubs/009695399/

 From a user perspective, the parts are all identical and support for 
common features is quite broad.  For example, threading support is 
optional, but you'd be hard pressed to find a Posix-compliant OS that 
didn't support it.  Beyond this issue of optional components (which 
again isn't much of an issue in practice), the things you'd expect to be 
implementation-defined are: struct layout, const values, etc.  None of 
this is visible to the user, but it's obviously an issue for someone 
porting Posix headers to D.


Sean