keys will be ordered the same between different runs of Perl.
The default behaviour is to randomise unless the PERL_HASH_SEED is set.
-If Perl has been compiled with the -DUSE_HASH_SEED_EXPLICIT the default
+If Perl has been compiled with C<-DUSE_HASH_SEED_EXPLICIT>, the default
behaviour is B<not> to randomise unless the PERL_HASH_SEED is set.
If PERL_HASH_SEED is unset or set to a non-numeric string, Perl uses
the pseudorandom seed supplied by the operating system and libraries.
If unset, each different run of Perl will have different ordering of
-the outputs of keys(), values, and each().
+the outputs of keys(), values(), and each().
See L<perlsec/"Algorithmic Complexity Attacks"> for more information.
+=item PERL_HASH_SEED_DEBUG
+
+Set to (anything) to display the value of the hash seed.
+
=item PERL_ROOT (specific to the VMS port)
A translation concealed rooted logical name that contains perl and the
In Perls 5.8.1 and later. If set to C<unsafe> the pre-Perl-5.8.0
signals behaviour (immediate but unsafe) is restored. If set to
-C<safe> the safe (or deferred) signals are used. See L<perlipc>.
+C<safe> the safe (or deferred) signals are used.
+See L<perlipc/"Deferred Signals (Safe signals)">.
=item PERL_UNICODE