iswblank
========

POSIX specification:
 https://pubs.opengroup.org/onlinepubs/9699919799/functions/iswblank.html

Gnulib module: iswblank

Portability problems fixed by Gnulib:

  * This function is missing on some platforms: Minix 3.1.8, IRIX 6.5, Solaris 9, mingw, MSVC 9, Android 4.4.

  * This function is declared but not defined on some platforms: IRIX 6.5.30.

  * This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.8.

Portability problems not fixed by Gnulib:

  * On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isblank, provided by Gnulib module c32isblank, operates on 32-bit wide characters and therefore does not have this limitation.