Re: (x)gethostname

[Bruno Haible]

Hi Simon,

> > But this is still not complete: The doc/functions/gethostname.texi file
> > says that the problem is that mingw lacks a gethostname function.
> 
> This is not the case now, and I'm not sure it ever was.  Where did that
> information come from?

I wrote it: I saw that the .m4 macro only looked whether the function was
missing and, based on the results of "nm" on various systems' libraries,
found that mingw was such a system. Evidently I didn't consider ws2_32 as
a system library.

> For reference, the Windows documentation for gethostname is:
> 
> http://msdn2.microsoft.com/en-us/library/ms738527.aspx

Thanks for the reference. So, to accomodate this function, we need a
rpl_gethostname that calls gethostname and accomodates
  1. for the need to call WSAStartup() before,
     This will require a new module 'sockets' in gnulib, because obviously
     we don't want to call WSAStartup() more than once.
  2. for the conversion from a WSA* error code to an <errno.h> error code.
     This will require, in particular, an 'errno' module and a modification
     to the 'strerror' module.

> The MSDN documentation says it is in winsock2.h and ws2_32, so I think
> we should use those headers/libraries until we know a reason to prefer
> winsock.h and wsock32.

Yes, I agree. Your sys_socket module already uses winsock2; there is no
point in mixing two different implementations of socket libraries.

> > And it is necessary to still override the function, in order to
> > WSAStartup before?
> 
> No, this doesn't seem to be necessary, at least under Wine.

I don't think that you can judge the behaviour of Windows by testing on
Wine. You know that Wine reimplements every DLL, so in particular Wine's
winsock is a different implementation that Windows winsock.

Bruno