Integrate from perlio; restructuring.

p4raw-id: //depot/perl@12554

diff --cc pod/perlapi.pod
index 6665191,75defb8..6a23c14
--- 1/pod/perlapi.pod
--- 2/pod/perlapi.pod
+++ b/pod/perlapi.pod
@@@ -2606,21 -2606,21 +2606,21 @@@ Like C<SvPV_nolen>, but converts sv to 
  =for hackers
  Found in file sv.h
  
--=item SvPVX
++=item SvPVx
  
--Returns a pointer to the physical string in the SV.  The SV must contain a
--string.
++A version of C<SvPV> which guarantees to evaluate sv only once.
  
--      char*   SvPVX(SV* sv)
++      char*   SvPVx(SV* sv, STRLEN len)
  
  =for hackers
  Found in file sv.h
  
--=item SvPVx
++=item SvPVX
  
--A version of C<SvPV> which guarantees to evaluate sv only once.
++Returns a pointer to the physical string in the SV.  The SV must contain a
++string.
  
--      char*   SvPVx(SV* sv, STRLEN len)
++      char*   SvPVX(SV* sv)
  
  =for hackers
  Found in file sv.h
@@@ -2827,19 -2827,19 +2827,19 @@@ false, defined or undefined.  Does not 
  =for hackers
  Found in file sv.h
  
--=item svtype
++=item SvTYPE
  
--An enum of flags for Perl types.  These are found in the file B<sv.h>
--in the C<svtype> enum.  Test these flags with the C<SvTYPE> macro.
++Returns the type of the SV.  See C<svtype>.
++
++      svtype  SvTYPE(SV* sv)
  
  =for hackers
  Found in file sv.h
  
--=item SvTYPE
--
--Returns the type of the SV.  See C<svtype>.
++=item svtype
  
--      svtype  SvTYPE(SV* sv)
++An enum of flags for Perl types.  These are found in the file B<sv.h>
++in the C<svtype> enum.  Test these flags with the C<SvTYPE> macro.
  
  =for hackers
  Found in file sv.h