realpath
========

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

Gnulib module: canonicalize-lgpl

Portability problems fixed by Gnulib:

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

  * This function does not allow for a NULL resolved parameter on some platforms: Mac OS X 10.5, FreeBSD 6.4, OpenBSD 4.4, Solaris 10.

  * This function does not always return an absolute path on some platforms: Solaris 10.

  * This function fails to detect trailing slashes on non-directories on some platforms: glibc 2.3.5.

  * This function fails to recognize non-directories followed .. on some platforms: cygwin.

  * This function misbehaves on consecutive slashes on some platforms: AIX 7.

Portability problems not fixed by Gnulib:

  * This function does not allow to determine the required size of output buffer; the use of a non-NULL resolved buffer is non-portable, since PATH_MAX, if it is defined, is nothing more than a guess.