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From: Alexei Starovoitov <ast@plumgrid.com>
Subject: Re: Why return E2BIG from bpf map update?
Date: Tue, 21 Jul 2015 14:34:39 -0700
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On 7/21/15 3:13 AM, Alex Gartrell wrote:
> But, the EINVAL errno has similarly been
> abused to death

there was a thread few month ago trying to come up with
a generic solution for aliased error codes, but unfortunately
nothing concrete came out of it.
The one I liked sounded that the kernel may be able to extend
syscall interface to return a string together with errno,
but it's quite hard to do at present.
May be extensions to vdso data writable by kernel can
improve the situation.