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    SubjectRe: [PATCH] console UTF-8 fixes
    On Tue, Jun 19, 2007 at 03:54:52PM +0200, Bodo Eggert wrote:

    > Does the FLUSH DTRT by design, or does it just shrink and hide the original
    > race?

    I haven't deeply studied this aspect of the source, don't know what
    _exactly_ this FLUSH does, but of course I have an inner feeling about this.
    Kind of this macro does the _real_ print on the screen. It actually calls
    vc->vc_sw->con_putcs, whereas I guess vc_sw refers to the particular
    implementation (vga, fb) and con_putcs might be doing the real job.

    Without these two new FLUSHes the behavior was very funny: applications
    (e.g. text editors) highlighed incorrect cells, but either switching between
    VTs, or gpming over these cells corrected the display. So the logical
    content behind the scenes (reflected by /dev/vcsa*) was maintained
    correctly, the bug is somewhere when the content is first displayed.

    I saw that this FLUSH was already used 3 times inside do_con_write(), I
    placed it here 2 more times (when changing color attr to inverse and when
    reverting to normal). I think it cannot hurt, and apparently it fixes the
    problem.

    But you may be right: yes, it might be a bug (or misfeature) in the FB code,
    too. Could you please look after it? I don't think I'd be able to do it and
    have time for this.

    > And why wasn't VGA affected, too?

    I guess tt must be some difference between the actual VGA and FB code that
    is called from here. I don't know whether it's a bug in FB or just some
    difference.

    Perhaps it's that the FB driver's con_putcs() call uses vc->vc_attr (the
    current attr for the console) for each char cell to be printed, instead of
    the own attr values of the cells themselves. Just an idea...



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