SvPV – string 

svpv.png
Picture Credit: Reini Urban - Perl Guts Illustrated
$s = "abcdefghijklmnopqrstuvwxyz";
SV = PV(0x8c7c20) at 0x8e7aa8
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x8e8eb0 "abcdefghijklmnopqrstuvwxyz"\0
  CUR = 26
  LEN = 32