+@item
+This function is missing on some platforms:
+glibc 2.3.6, MacOS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8,
+AIX 5.1, HP-UX 11, IRIX 6.5, OSF/1 5.1, Cygwin 1.5.x, mingw, Interix 3.5, BeOS.
+But the replacement function is not safe to be used in libraries and is not multithread-safe.
+@item
+On platforms where @code{off_t} is a 32-bit type, @code{fstatat} may
+not correctly report the size of files or block devices larger than 2
+GB. (Cf. @code{AC_SYS_LARGEFILE}.)
+@item
+On some platforms, @code{fstatat(fd,"file/",buf,flag)} succeeds instead of
+failing with @code{ENOTDIR}.
+Solaris 9.
+@item
+For symlinks, when the argument ends in a slash, some platforms don't
+dereference the argument:
+Solaris 9.