IV
PerlIOBase_close(pTHX_ PerlIO *f)
{
    IV code = -1;
    if (PerlIOValid(f)) {
        PerlIO *n = PerlIONext(f);
        code = PerlIO_flush(f);
        PerlIOBase(f)->flags &=
           ~(PERLIO_F_CANREAD | PERLIO_F_CANWRITE | PERLIO_F_OPEN);
        while (PerlIOValid(n)) {
            const PerlIO_funcs * const tab = PerlIOBase(n)->tab;
            if (tab && tab->Close) {
                if ((*tab->Close)(aTHX_ n) != 0)
                    code = -1;
                break;
            }
            else {
                PerlIOBase(n)->flags &=
                    ~(PERLIO_F_CANREAD | PERLIO_F_CANWRITE | PERLIO_F_OPEN);
            }
            n = PerlIONext(n);
        }
    }
    else {
        SETERRNO(EBADF, SS_IVCHAN);
    }
    return code;
}