[R-sig-Debian] Change Rscript and `/usr/lib/R/bin/R` relation

[Dirk Eddelbuettel]

On 12 February 2016 at 15:11, Alexey Zaharov wrote:
| Probably you would like to know, that I have managed to solve the problem 
| by using `schroot`.

Good call.  We (as in Debian package managers) do something very similar for
package building, of course. And there is an entire infrastructure for it.

| It can attach current user `home` folder to `rootfs` from `chroot` where.
| 
| After I have configured the `trusty64`, I have just created a clone.
| Inside the clone I have installed another version of R from CRAN repo.
| <--------------------------------START------------->
| root at chroot-test:/# schroot -l
| chroot:trusty64
| chroot:trusty64_clone
| 
| 
| $ cat /etc/schroot/chroot.d/trusty64.conf 
| [trusty64]
| description=Ubuntu 14.04 Trusty Tahr
| directory=/test/schroot/trusty64
| users=quant
| type=directory
| profile=desktop
| #personality=linux
| preserve-environment=true
| root-groups=root
| 
| $ cat /etc/schroot/chroot.d/trusty64_clone.conf 
| [trusty64_clone]
| description=Ubuntu 14.04 Trusty Tahr
| directory=/test/schroot/trusty64
| users=quant
| type=directory
| profile=desktop
| #personality=linux
| preserve-environment=true
| root-groups=root
| 
| root at chroot-test:/etc# debootstrap --variant=minbase --arch amd64 trusty /
| test/schroot/trusty64/ http://archive.ubuntu.com/ubuntu/
| 
| 
| root at chroot-test:/etc# schroot -c trusty64 -u quant
| root at chroot-test:/etc# schroot -c trusty64_clone -u quant
| <--------------------------------END--------------->

That works. The key is that (as I said earlier) the path from / to the R
binaries and libs are 'fixed' at compile time -- but you can run several
virtual environment on the box to 'fake' different / path.  Docker is one
(portable) way and we offer a bunch of R containers for it already, and
within the Debian/Ubuntu world one can of course use different chroot-based
solutions: dchroot, schroot, pbuilder, cowbuilder, ...  Thanks for pointing
that last part out.

Dirk

-- 
http://dirk.eddelbuettel.com | @eddelbuettel | edd at debian.org