getc
====

POSIX specification:
 http://www.opengroup.org/onlinepubs/9699919799/functions/getc.html

Gnulib module: stdio, nonblocking

Portability problems fixed by Gnulib module stdio, together with module nonblocking:

  * When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw.

Portability problems not fixed by Gnulib:

  * On Windows platforms (excluding Cygwin), this function does not set errno upon failure.