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    SubjectRe: Linux 3.3-rc5
    On Tue, Feb 28, 2012 at 11:29 AM, Andreas Schwab <schwab@linux-m68k.org> wrote:
    >
    > Originally the garbage looked like this:
    >
    > #define I8K_BIOS_VERSION       _IOR ('i', 0x80, 4)
    > #define I8K_MACHINE_ID         _IOR ('i', 0x81, 16)
    > #define I8K_POWER_STATUS       _IOR ('i', 0x82, sizeof(int))
    > #define I8K_FN_STATUS          _IOR ('i', 0x83, sizeof(int))
    > #define I8K_GET_TEMP           _IOR ('i', 0x84, sizeof(int))
    > #define I8K_GET_SPEED          _IOWR('i', 0x85, sizeof(int))
    > #define I8K_GET_FAN            _IOWR('i', 0x86, sizeof(int))
    > #define I8K_SET_FAN            _IOWR('i', 0x87, sizeof(int)*2)
    >
    > Later they were modified by "[PATCH] use size_t for the broken ioctl
    > numbers" and "Fix more ioctl _IOR/_IOW misusage." (see tglx's history
    > tree).

    Ahh, yes. That wasn't the only driver that did the "sizeof" by hand,
    and as a result got "size_t" when the (nested) *real* sizeof then
    happened.

    That explains the history behind the garbage.

    ioctl numbering have always been pretty painful. Oh, how I wish they
    had been ASCII strings rather than random binary blobs. But that's the
    way things are (and we certainly screwed up a few /proc files too, so
    it's not like using text fixes all potential for screwing up)

    Linus
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