[Haifux] Telling the kernel business is closed (my weekly riddle)

[Nadav Har'El]

On Mon, Jun 27, 2011, Eli Billauer wrote about "[Haifux] Telling the kernel business is closed (my weekly riddle)":
> invocation of read(), write(), and other relevant methods. Maybe also 
> before returning a successful value. If the flag is set ( = problem 
> detected) return some -EDROPDEAD, so that application software reacts, 
> and maybe someone will go to /var/log/messages to get a better idea of 
> what happened. (I think I'll settle for -ENODEV)

ENODEV makes sense for open(2), but not for read(2), write(2) or ioctl(2).

For read(2) or write(2), I'd use EIO. For ioctl(2), I don't know what to use -
the manual page doesn't list EIO; Perhaps your ioctl(2) can return the failure
announcement as part of its normal return value, and don't fail the actual
ioctl?

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Nadav Har'El                        |      Tuesday, Jun 28 2011, 27 Sivan 5771
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