else {
open(CPP,"$cpp_file") or die "$0: Can't read preprocessed file $cpp_file: $!\n";
}
-%checkh = map { $_,1 } qw( thread bytecode byterun proto );
+%checkh = map { $_,1 } qw( thread bytecode byterun proto perlio );
$ckfunc = 0;
LINE: while (<CPP>) {
while (/^#.*vmsish\.h/i .. /^#.*perl\.h/i) {