"readlink" command also exists under OS X but with a completely different syntax than under Linux, so just use "pwd -P" to get the physical path name instead, this should hopefully work everywhere as it's POSIX. Closes #14796. git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72879 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775