+=head2 NDBM_File and ODBM_File do not work on FAT filesystems
+
+Do not use NDBM_File or ODBM_File on FAT filesystem. They can be
+built on a FAT filesystem, but many tests will fail:
+
+ ../ext/NDBM_File/ndbm.t 13 3328 71 59 83.10% 1-2 4 16-71
+ ../ext/ODBM_File/odbm.t 255 65280 ?? ?? % ??
+ ../lib/AnyDBM_File.t 2 512 12 2 16.67% 1 4
+ ../lib/Memoize/t/errors.t 0 139 11 5 45.45% 7-11
+ ../lib/Memoize/t/tie_ndbm.t 13 3328 4 4 100.00% 1-4
+ run/fresh_perl.t 97 1 1.03% 91
+
+If you intend to run only on FAT (or if using AnyDBM_File on FAT),
+run Configure with the -Ui_ndbm and -Ui_dbm options to prevent
+NDBM_File and ODBM_File being built.
+
+With NTFS (and CYGWIN=ntsec), there should be no problems even if
+perl was built on FAT.
+
+=head2 C<fork()> failures in io_* tests
+
+A C<fork()> failure may result in the following tests failing:
+
+ ext/IO/lib/IO/t/io_multihomed.t
+ ext/IO/lib/IO/t/io_sock.t
+ ext/IO/lib/IO/t/io_unix.t
+
+See comment on fork in L<Miscellaneous> below.
+