Re: mingw and AC_SYS_LARGEFILE

[Jim Meyering]

Bruno Haible wrote:
> Here's a proposed patch for Large File Support for native Windows platforms.
> Tested on mingw, mingw64 (32-bit), MSVC 9.
>
> It turns out there's nothing to do with open(), creat() - because there is
> no need for O_LARGEFILE on Windows - and also nothing to do with fopen(),
> fgetpos(), fsetpos() - because fpos_t is already 64-bit on Windows -.
>
> Opinions? Objections? Jim, in particular it touches the 'ftruncate' module,
> which is yours.

Hi Bruno,

Thanks for all the work.
The new code looks fine, and I'm sure you've tested it
thoroughly, but the new names, gl_LARGEFILE and USE_64_BIT_OFF_T
sound like things that one would use and expect to be set (resp.)
even on non-Windows systems.  What do you think about changing
the names to make it clear that they are useful only when building
on mingw?

> --- m4/largefile.m4.orig      Sat Apr 14 22:55:20 2012
...
> +# Enable large files on systems where this is implemented by Gnulib, not by 
> the
> +# system headers.
> +AC_DEFUN([gl_LARGEFILE],
> +[
> +  AC_REQUIRE([AC_CANONICAL_HOST])
> +  case "$host_os" in
> +    mingw*) # native Windows
> +      USE_64_BIT_OFF_T=1 ;;
> +    *)
> +      USE_64_BIT_OFF_T=0 ;;
> +  esac
> +])