Re: isatty fails on Windows 8

[Eli Zaretskii]

> Date: Thu, 20 Dec 2012 19:02:03 -0500
> From: Michael Goffioul <address@hidden>
> 
> We've got a bug report in octave [1] that seems to indicate that gnulib's
> replacement of isatty is incorrect on Windows 8 (it's fine up to Windows
> 7). Looking at the implementation, it first calls the Windows _isatty
> version, then checks the last 2 bits of the handle associated with the file
> descriptor, based on the assumption described in [2] (a console HANDLE is
> not a multiple of 4). It seems that this last assumption is not valid
> anymore on Windows 8.

Does the following work on Windows 8?

  #define ISATTY(fd) (isatty(fd) && lseek(fd,SEEK_CUR,0) == -1)

and then use ISATTY instead of isatty.

(The lseek test is to reject other character devices, most prominently
the null device, with MS implementation of isatty doesn't reject.)