[dpdk-dev] [PATCH] kni: fix building on Ubuntu-hybrids

[Thomas Monjalon]

2014-10-23 16:39, Alexander Guy:
> In the case where a userspace reports itself as Ubuntu, but the
> kernel isn't providing the expected version signature interface,
> turn off Ubuntu specializations.
> 
> This situation happens often enough in development environments,
> and with multi-distribution build servers (e.g. chroot, containers).
[...]
> -ifeq ($(shell lsb_release -si 2>/dev/null),Ubuntu)
> +ifeq ($(shell test -f /proc/version_signature && lsb_release -si 2>/dev/null),Ubuntu)

Please, could explain what is the file /proc/version_signature and why
it can be a check for Ubuntu kernel?

Thanks
-- 
Thomas