Messages in this thread | | | Date | Tue, 03 Mar 2009 20:38:37 -0800 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH 5/5] tracing: add binary buffer files for use with splice |
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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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