Re: Extended error reporting to user space?

From: Dr. David Alan Gilbert
Date: Sat Feb 20 2010 - 19:09:22 EST


* Andi Kleen (andi@xxxxxxxxxxxxxx) wrote:
> > I'd wondered about some form of halfway house where the error
> > value is expanded but could be truncated for compatibility - i.e.
>
> Who would do the truncation?

I'd assumed something like the code in entry*.S or equivalent for
existing syscalls, but have another entry that would pass it through
to a newer libc that new how to handle it.

> > if at the moment we had:
> >
> > return -EINVAL;
> >
> > it would become:
> >
> > return ERRORNUM(EINVAL, BADLENGTH);
>
> x86 only has about 12 bits in the current ABI btw.

Ah yes I can see that now, hmm.

Dave
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