>Seems like there should be a library routine to parse stty flags,
>probably in libtuil...

BSD/OS has one (indeed, in libutil) ... in the interest of
compatibility :-) here is the interface.

/*
 * Set the given stty(1)-style flags in the given termios structure.
 * We return 0 for success, -1 for failure.
 * If failp is nonzero, *failp is set to the flag that didn't parse
 * or had an illegal value, otherwise 0.
 */
int
cfsetterm(t, flags, failp)
	struct termios *t;
	const char *flags;
	char **failp;
{

Here `flags' is the value from the :ms=: string.  (Not sure if SunOS
uses `ms'...)

Chris