Comment 106 for bug 1522675

I'm getting this error on Ubuntu 17.10:
W: Download is performed unsandboxed as root as file '/root/.synaptic/tmp//tmp_cl' couldn't be accessed by user '_apt'. - pkgAcquire::Run (13: Permission denied)

I have a user _apt, and it owns /var/lib/update-notifier/package-data-downloads/partial/

It looks like the problems are 2-fold:
1. The double-slash in '/root/.synaptic/tmp//tmp_cl' is equivalent to /tmp_cl, isn't it? That doesn't exist, and probably shouldn't. The double-slash should probably be a single slash.
2. Why is _apt supposed to be able to access anything in /root? If /root/.synaptic/tmp is a special case, then somebody or some program needs to change its ownership. Right now it's:
drwx------ 2 root root /root/.synaptic/tmp