Re: replacing folders with symlinks (pre vs pretrans)
On 05/28/2013 06:50 PM, Stanislav Ochotnicky wrote:
Quoting Panu Matilainen (2012-09-21 10:17:27)
> A directory (empty or not) can't be automatically replaced by anything
> else (symlink or otherwise) in the existing rpm versions. If absolutely
> necessary, it can be accomplished by doing the necessary renames and
> symlinks in "%pretrans -p <lua>" scriptlet, but that should be only
seen
> as the last resort as its not exactly a safe operation.
This used to work in %pre scriptlet as well. It seems like RPM is now doing some
additional checks and it will not even get to the point of %pre scriptlet. As
far as I can see for F17/F18 %pre scriptlet will work, but F19+ %pretrans has to
be used, correct?
%pre was never correct for the task because it means rpm wont know about
the change, which can cause side-effects like files from the new package
removed on cleanup of the older package, junk left behind etc. What
exactly happens depends on the details.
And yes, rpm >= 4.11 enforces use of %pretrans for the purpose as it
detects the issue early on, whereas older versions just merrily go ahead
and likely ends up making a mess during the transaction.
Since I *knew* we used %pre for this exact problem before, I have
used it and
it broke upgrade paths[1]. I assume just rewriting %pre[2] into following
%pretrans will work:
for key, dir in pairs({"boot", "conf"}) do
path = "%{_datadir}/%{name}/" .. dir
if posix.readlink(path) then
os.remove(path)
end
end:
It certainly seemed to work now, but I wonder if I am just missing something else.
Yup, something like that.
- Panu -