make sure USE_THREADS is defined so external apps work

[p5sagit/p5-mst-13.2.git] / pod / perlvar.pod

diff --git a/pod/perlvar.pod b/pod/perlvar.pod
index 3f4c2f5..d723271 100644 (file)
--- a/pod/perlvar.pod
+++ b/pod/perlvar.pod
@@ -1062,6 +1062,10 @@ loaded also:
     use lib '/mypath/libdir/';
     use SomeMod;
 
+You can also insert hooks into the file inclusion system by putting Perl
+code directly into @INC.  Those hooks may be subroutine references, array
+references or blessed objects.  See L<perlfunc/require> for details.
+
 =item @_
 
 Within a subroutine the array @_ contains the parameters passed to that
@@ -1076,6 +1080,11 @@ value is the location of the file found.  The C<require>
 operator uses this hash to determine whether a particular file has
 already been included.
 
+If the file was loaded via a hook (see L<perlfunc/require> for a
+description of these hooks), a fake filename is inserted into %INC. It
+looks like F</loader/0x81095c8/Foo.pm>, where the hexadecimal number
+corresponds to the reference that was put in @INC.
+
 =item %ENV
 
 =item $ENV{expr}