TTY_CHARMASK
#define ISALPHA(c) (char_type[(c) & TTY_CHARMASK] & ALPHA)
CLR(c, ~TTY_CHARMASK);
((ISSET(c, TTY_CHARMASK) <= 037 && c != '\t' && c != '\n') ||
ISSET(c, TTY_CHARMASK) == 0177)) {
CLR(c, ~TTY_CHARMASK);
CLR(c, ~TTY_CHARMASK);
cl->c_data[i] = (short)c & (TTY_QUOTE | TTY_CHARMASK);
c &= TTY_CHARMASK;
c &= TTY_CHARMASK;
c & TTY_CHARMASK);
__func__, NG_NODE_NAME(sc->node), c & TTY_CHARMASK,
sc->ibuf[sc->got ++] = (c & TTY_CHARMASK);
c &= TTY_CHARMASK;