realpath (GNU Gnulib)

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, macOS 11.1, OpenBSD 6.0.
This function fails to recognize non-directories or symlinks to non-directories followed by ‘..’ on some platforms: Cygwin 2.9.
This function misbehaves on consecutive slashes on some platforms: musl libc 1.2.2, 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.