PerlIOBase_noop_fail
PerlIOBase_noop_ok
PerlIOBase_popped
+ PerlIOBase_pushed
PerlIOBase_read
PerlIOBase_setlinebuf
PerlIOBase_unread
PerlIOBuf_unread
PerlIOBuf_write
PerlIO_allocate
+ PerlIO_apply_layera
PerlIO_apply_layers
PerlIO_arg_fetch
PerlIO_debug