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    SubjectRe: Improving the Unix API
    >> (clri didn't work?)
    > Never heard about clri (was under Linux).

    May not have existed, then, which *would* explain it. :-)

    >>> Another problem was the ability to change the mount status of a
    >>> partition from read-write to read-only or to unmounted,
    >> See NetBSD (and presumably other BSD) "mount -o update,rdonly"
    >> and/or "umount -f".
    > If you re-read the original message, the problem is what to do about
    > processes with open file descriptors on the partition: stop them at
    > once? stop them at first file access? block them instead? kill them?

    Yes, that's the most difficult part.

    The NetBSD manpage doesn't say what happens if you "mount -o
    update,force,rdonly" when there are writeable descriptors open onto the
    filesystem, and then try to use those fds. I would assume further
    attempts to write would produce errors (EROFS?), unless of course the
    filesystem has been re-remounted read/write.

    The manpage for umount says

    -f The filesystem is forcibly unmounted. Active special devices
    continue to work, but all other files return errors if further
    accesses are attempted.

    I haven't looked at the relevant kernel code to see what *really*
    happens.

    > How will you allow for such large table-walking to be compatible with
    > real-time kernel response?

    *What* large table-walking? All this means you have to do is have
    every write check the relevant mount point to see if it's mounted
    read-only, for downgrading remounts, and mark the filesystem as gone,
    for forced unmounts. (I suspect this is what deadfs is for.)

    >>> I intend to put free unices in competition [...]
    >> Reasonable as this sounds, I think the last thing we need is yet
    >> another ground on which one free-unix can be doing the "nana nana
    >> boo boo" taunt at another.
    > Competition is _not_ about taunting each other for pride;

    I know this. I even think most of the people involved know it.

    But there seem to be a few - not many, but very poisonous - who seem to
    take any competition - indeed, almost any *difference* - as an
    opportunity for "we're better than you" egoboo.

    der Mouse

    mouse@rodents.montreal.qc.ca
    7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B

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