[Toybox] Multiple OS support in tests

[Ed Maste]

On Fri, 18 Jan 2019 at 14:14, Rob Landley <rob at landley.net> wrote:
>
>   $ sysctl -n kern.hostname
>   sysctl: cannot stat /proc/sys/kern/hostname: No such file or directory
>   $ toybox sysctl -n kernel.hostname
>   halfbrick
>
> You know... I think ubuntu's error message is clearer. :)
>
> Does the longer name work on BSD, or just the short one?

Just the short one.

% sysctl -n kernel.hostname
sysctl: unknown oid 'kernel.hostname'
% sysctl -n kern.hostname
volta

> I could do a tests-portability.sh but let's hold off and collect a few and try
> to actually fix them first...

Sounds good to me. For now I'm just changing them to run on FreeBSD in
my tree as I find them, breaking Linux in the process, to get a better
idea of the scope.

The next one is stat - it seems "stat -c %i" becomes "stat -f %i" but
other fields (e.g. %s) don't exist.