Re: [PATCH 5/5] tracing: add binary buffer files for use with splice

[H. Peter Anvin]

Steven Rostedt wrote:
> > Conventionally a read() system call will return the number of bytes
> > copied, and will only return -EFOO if the number of bytes copied was
> > zero.
> >
> > Lots of parts of the kernel break this, but it's usually device drivers
> > and scruffy pseudo files, in which case a partial file read doesn't
> > make much sense.  This doesn't make the broken behaviour right, but at
> > least we have a bit of a weaselly excuse in that case.
>
> I just went by the read man page:
>
>        EFAULT buf is outside your accessible address space.

Yes, and that is the correct value if no bytes were copied.

	-hpa

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