=over

=item ${^SAFE_LOCALES}
X<${^SAFE_LOCALES}>

Reflects if safe locale operations are available to this perl (when the
value is 1) or not (the value is 0).  This variable is always 1 if the
perl has been compiled without threads.  It is also 1 if this perl is
using thread-safe locale operations.  Note that an individual thread may
choose to use the global locale (generally unsafe) by calling
L<perlapi/switch_to_global_locale>.  This variable currently is still
set to 1 in such threads.

This variable is read-only.

This variable was added in Perl v5.28.0.

=back