On a fresh container of 1.x, running /opt/R/1.0.0/bin/R (or other versions):

> list.files("/opt/R")
character(0)
> list.files("/usr/lib/perl")
character(0)

Is this a permissions issue? I'm logged in as root and bash ls returns the expected result. Other directories also return a normal result:

> list.files("/usr/lib/mime/packages/")
[1] "debianutils" "groff-base"  "less"        "tar"         "util-linux"