isatty (GNU Gnulib)

Gnulib module: isatty

Portability problems fixed by Gnulib:

This function is declared in a different header file (namely, <io.h>) on some platforms: MSVC 14.
On native Windows, this function also returns true for character devices such as NUL.
On native Windows, this function returns false for Cygwin consoles.
This function crashes when invoked with invalid arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib: