FIONREAD and IRIX 6

[Benjamin Kosnik]

>There are 4 27_io/basic_filebuf/sgetn/char failures on IRIX:
>
>   http://gcc.gnu.org/ml/gcc-testresults/2004-01/msg01339.html
>
>These are due to IRIX's FIONREAD taking a "size_t *" rather than "int *"
>argument.  __basic_file<char>::showmanyc() ends up returning the high word
>of the size_t, which is 0 for these tests.

Thanks for tracking this down.

>What's the preferred way of handling this sort thing?  Is it OK to
>add a new #define to config/os/irix/irix6.5/os_defines.h and use
>that to alter the type in showmanyc()?  If so, what sort of name
>would you suggest?

This sounds acceptable. You can either do something like
_GLIBCXX_FIONREAD_FIXUP or whatever, as long as it's guarded correctly.

-benjamin