dirname
=======

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

Gnulib module: ---

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  * This function is missing on some platforms: IRIX 6.5, mingw, MSVC 14.

  * dirname assumes file names in POSIX syntax; it does not work with file names in Windows syntax.

The Gnulib module dirname provides similar API, with functions dir_name and mdir_name, that also works with Windows file names.