Portability problems fixed by Gnulib:
@itemize
@item
+This function is declared in different header files (namely, @code{<io.h>} or
+@code{<direct.h>}) on some platforms:
+mingw, MSVC 9.
+@item
When the argument ends in a slash, the function call fails on some platforms.
@item
This function mistakenly succeeds on @samp{mkdir("d/./",mode)} on
some platforms:
-Cygwin 1.5.x, mingw.
+Cygwin 1.5.x, mingw, MSVC 9.
@item
On Windows platforms (excluding Cygwin), this function is called @code{_mkdir}
and takes only one argument. The fix (without Gnulib) is to define a macro