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diff --git a/pod/perlintern.pod b/pod/perlintern.pod
index b0aab33..c9cb5e7 100644
--- a/pod/perlintern.pod
+++ b/pod/perlintern.pod
@@ -1,23 +1,287 @@
 =head1 NAME
 
-perlintern - autogenerated documentation of purely B<internal> 
+perlintern - autogenerated documentation of purely B<internal>
 		 Perl functions
 
 =head1 DESCRIPTION
 
-This file is the autogenerated documentation of functions in the 
+This file is the autogenerated documentation of functions in the
 Perl interpreter that are documented using Perl's internal documentation
-format but are not marked as part of the Perl API. In other words, 
+format but are not marked as part of the Perl API. In other words,
 B<they are not for use in extensions>!
 
+
+=head1 Global Variables
+
 =over 8
 
+=item PL_DBsingle
+
+When Perl is run in debugging mode, with the B<-d> switch, this SV is a
+boolean which indicates whether subs are being single-stepped.
+Single-stepping is automatically turned on after every step.  This is the C
+variable which corresponds to Perl's $DB::single variable.  See
+C<PL_DBsub>.
+
+	SV *	PL_DBsingle
+
+=for hackers
+Found in file intrpvar.h
+
+=item PL_DBsub
+
+When Perl is run in debugging mode, with the B<-d> switch, this GV contains
+the SV which holds the name of the sub being debugged.  This is the C
+variable which corresponds to Perl's $DB::sub variable.  See
+C<PL_DBsingle>.
+
+	GV *	PL_DBsub
+
+=for hackers
+Found in file intrpvar.h
+
+=item PL_DBtrace
+
+Trace variable used when Perl is run in debugging mode, with the B<-d>
+switch.  This is the C variable which corresponds to Perl's $DB::trace
+variable.  See C<PL_DBsingle>.
+
+	SV *	PL_DBtrace
+
+=for hackers
+Found in file intrpvar.h
+
+=item PL_dowarn
+
+The C variable which corresponds to Perl's $^W warning variable.
+
+	bool	PL_dowarn
+
+=for hackers
+Found in file intrpvar.h
+
+=item PL_last_in_gv
+
+The GV which was last used for a filehandle input operation. (C<< <FH> >>)
+
+	GV*	PL_last_in_gv
+
+=for hackers
+Found in file thrdvar.h
+
+=item PL_ofs_sv
+
+The output field separator - C<$,> in Perl space.
+
+	SV*	PL_ofs_sv
+
+=for hackers
+Found in file thrdvar.h
+
+=item PL_rs
+
+The input record separator - C<$/> in Perl space.
+
+	SV*	PL_rs
+
+=for hackers
+Found in file thrdvar.h
+
+
+=back
+
+=head1 GV Functions
+
+=over 8
+
+=item is_gv_magical
+
+Returns C<TRUE> if given the name of a magical GV.
+
+Currently only useful internally when determining if a GV should be
+created even in rvalue contexts.
+
+C<flags> is not used at present but available for future extension to
+allow selecting particular classes of magical variable.
+
+	bool	is_gv_magical(char *name, STRLEN len, U32 flags)
+
+=for hackers
+Found in file gv.c
+
+
+=back
+
+=head1 IO Functions
+
+=over 8
+
+=item start_glob
+
+Function called by C<do_readline> to spawn a glob (or do the glob inside
+perl on VMS). This code used to be inline, but now perl uses C<File::Glob>
+this glob starter is only used by miniperl during the build process.
+Moving it away shrinks pp_hot.c; shrinking pp_hot.c helps speed perl up.
+
+	PerlIO*	start_glob(SV* pattern, IO *io)
+
+=for hackers
+Found in file doio.c
+
+
+=back
+
+=head1 Pad Data Structures
+
+=over 8
+
+=item CvPADLIST
+
+CV's can have CvPADLIST(cv) set to point to an AV.
+
+For these purposes "forms" are a kind-of CV, eval""s are too (except they're
+not callable at will and are always thrown away after the eval"" is done
+executing).
+
+XSUBs don't have CvPADLIST set - dXSTARG fetches values from PL_curpad,
+but that is really the callers pad (a slot of which is allocated by
+every entersub).
+
+The CvPADLIST AV has does not have AvREAL set, so REFCNT of component items
+is managed "manual" (mostly in op.c) rather than normal av.c rules.
+The items in the AV are not SVs as for a normal AV, but other AVs:
+
+0'th Entry of the CvPADLIST is an AV which represents the "names" or rather
+the "static type information" for lexicals.
+
+The CvDEPTH'th entry of CvPADLIST AV is an AV which is the stack frame at that
+depth of recursion into the CV.
+The 0'th slot of a frame AV is an AV which is @_.
+other entries are storage for variables and op targets.
+
+During compilation:
+C<PL_comppad_name> is set the the the names AV.
+C<PL_comppad> is set the the frame AV for the frame CvDEPTH == 1.
+C<PL_curpad> is set the body of the frame AV (i.e. AvARRAY(PL_comppad)).
+
+Itterating over the names AV itterates over all possible pad
+items. Pad slots that are SVs_PADTMP (targets/GVs/constants) end up having
+&PL_sv_undef "names" (see pad_alloc()).
+
+Only my/our variable (SVs_PADMY/SVs_PADOUR) slots get valid names.
+The rest are op targets/GVs/constants which are statically allocated
+or resolved at compile time.  These don't have names by which they
+can be looked up from Perl code at run time through eval"" like
+my/our variables can be.  Since they can't be looked up by "name"
+but only by their index allocated at compile time (which is usually
+in PL_op->op_targ), wasting a name SV for them doesn't make sense.
+
+The SVs in the names AV have their PV being the name of the variable.
+NV+1..IV inclusive is a range of cop_seq numbers for which the name is valid.
+For typed lexicals name SV is SVt_PVMG and SvSTASH points at the type.
+
+If SvFAKE is set on the name SV then slot in the frame AVs are
+a REFCNT'ed references to a lexical from "outside".
+
+If the 'name' is '&' the the corresponding entry in frame AV
+is a CV representing a possible closure.
+(SvFAKE and name of '&' is not a meaningful combination currently but could
+become so if C<my sub foo {}> is implemented.)
+
+	AV *	CvPADLIST(CV *cv)
+
+=for hackers
+Found in file cv.h
+
+
+=back
+
+=head1 Stack Manipulation Macros
+
+=over 8
+
+=item djSP
+
+Declare Just C<SP>. This is actually identical to C<dSP>, and declares
+a local copy of perl's stack pointer, available via the C<SP> macro.
+See C<SP>.  (Available for backward source code compatibility with the
+old (Perl 5.005) thread model.)
+
+		djSP;
+
+=for hackers
+Found in file pp.h
+
+=item LVRET
+
+True if this op will be the return value of an lvalue subroutine
+
+=for hackers
+Found in file pp.h
+
+
+=back
+
+=head1 SV Manipulation Functions
+
+=over 8
+
+=item report_uninit
+
+Print appropriate "Use of uninitialized variable" warning
+
+	void	report_uninit()
+
+=for hackers
+Found in file sv.c
+
+=item sv_add_arena
+
+Given a chunk of memory, link it to the head of the list of arenas,
+and split it into a list of free SVs.
+
+	void	sv_add_arena(char* ptr, U32 size, U32 flags)
+
+=for hackers
+Found in file sv.c
+
+=item sv_clean_all
+
+Decrement the refcnt of each remaining SV, possibly triggering a
+cleanup. This function may have to be called multiple times to free
+SVs which are in complex self-referential hierarchies.
+
+	I32	sv_clean_all()
+
+=for hackers
+Found in file sv.c
+
+=item sv_clean_objs
+
+Attempt to destroy all objects not yet freed
+
+	void	sv_clean_objs()
+
+=for hackers
+Found in file sv.c
+
+=item sv_free_arenas
+
+Deallocate the memory used by all arenas. Note that all the individual SV
+heads and bodies within the arenas must already have been freed.
+
+	void	sv_free_arenas()
+
+=for hackers
+Found in file sv.c
+
+
 =back
 
 =head1 AUTHORS
 
-The autodocumentation system was originally added to the Perl core by 
-Benjamin Stuhl. Documentation is by whoever was kind enough to 
+The autodocumentation system was originally added to the Perl core by
+Benjamin Stuhl. Documentation is by whoever was kind enough to
 document their functions.
 
 =head1 SEE ALSO