Re: O_NONBLOCK is NOOP on block devices
From: Alan Cox
Date: Wed Mar 03 2010 - 06:47:34 EST
> If O_NONBLOCK is meaningful whatsoever (see man page docs for
> semantics) against block devices, one would expect a nonblocking io
The manual page says "When possible, the file is opened in non-blocking
mode" . Your write is probably not blocking - but the memory allocation
for it is forcing other data to disk to make room. ie it didn't block it
was just "slow".
O_NONBLOCK on a regular file does influence how it responds to leases and
> probably be documented for clarity and it would be straight forward
> for it to return an error if these contradictory behaviors are
> simultaneously specified, unintentionally of course.
and risk breaking existing apps.
> Thoughts anyone?
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/