Re: Arg preserve_echo_area is ignored in redisplay_internal ()

[Eli Zaretskii]

> From: Kenichi Handa <address@hidden>
> Date: Fri, 08 Jan 2010 21:34:22 +0900
> 
> In xdisp.c, redisplay_internal has the arg
> preserve_echo_area but it is not used in that function.
> Does it mean that the arg is obsolete now, or that there's
> some bug in the function?

Neither.  It's a provision for future development, as the commentary
says:

    /* If PRESERVE_ECHO_AREA is nonzero, it means this redisplay is not in
       response to any user action; therefore, we should preserve the echo
       area.  (Actually, our caller does that job.)  Perhaps in the future
       avoid recentering windows if it is not necessary; currently that
       causes some problems.  */