Apd |STRLEN |sv_len_utf8 |SV* sv
Apd |void |sv_magic |SV* sv|SV* obj|int how|const char* name \
|I32 namlen
+Apd |MAGIC *|sv_magicext |SV* sv|SV* obj|int how|MGVTBL *vtbl \
+ | const char* name|I32 namlen
Apd |SV* |sv_mortalcopy |SV* oldsv
Apd |SV* |sv_newmortal
Apd |SV* |sv_newref |SV* sv