=for apidoc Am|char*|SvEND|SV* sv
Returns a pointer to the spot just after the last character in
the string which is in the SV, where there is usually a trailing
-C<NUL> byte (even though Perl scalars do not strictly require it).
+C<NUL> character (even though Perl scalars do not strictly require it).
See C<SvCUR>. Access the character as *(SvEND(sv)).
Warning: If C<SvCUR> is equal to C<SvLEN>, then C<SvEND> points to
Set the value of the NV pointer in sv to val. See C<SvIV_set>.
=for apidoc Am|void|SvPV_set|SV* sv|char* val
-Set the value of the PV pointer in sv to val. See also C<SvIV_set>.
+Set the value of the PV pointer in C<sv> to the C<NUL>-terminated string
+C<val>. See also C<SvIV_set>.
Beware that the existing pointer may be involved in copy-on-write or other
mischief, so do C<SvOOK_off(sv)> and use C<sv_force_normal> or