C_QUIT
{"quit", C_SH(C_QUIT), MD_CHAR},
case C_QUIT:
s[C_QUIT] = td->c_cc[VQUIT];
td->c_cc[VQUIT] = s[C_QUIT];
ex_cinit(&cmd, C_QUIT, 0, OOBLNO, OOBLNO, 0, NULL);