[Fedora-r-devel-list] R-java and R-java-devel

[Pierre-Yves]

On Tue, 2009-04-07 at 18:53 +0200, Martyn Plummer wrote:
> On Tue, 2009-04-07 at 12:59 +0200, Pierre-Yves wrote:
> > On Tue, 2009-04-07 at 12:09 +0200, Martyn Plummer wrote:
> > 
> > > Setting R_HOME in the environment before launching R is the wrong
> > > thing to do. 
> > Just out of curiosity, why ? R_HOME should be coherent between the
> > environment and R itself, through a warning if they are different makes
> > sense (IMHO), but if they are the same what is the problem ?
> 
> People can and do have multiple R installations. Most of these people
> are developers, but we also encourage users to download and test beta
> releases. You are currently breaking developer builds by setting R_HOME
> to point to the Fedora RPM.  Of course, the breakage is relatively
> minor, and takes the form of annoying warnings, but those warnings were
> put there for a reason.
> 
> The user is not meant to set R_HOME. The system administrator is
> certainly not meant to set R_HOME.  R_HOME is meant to be set by the
> application that starts the R engine, and it does so in its own shell so
> that there are no side effects. This allows multiple versions of R to
> coexist on the same system.
> 
> The only reason that the warning is silenced when the R_HOME environment
> variable matches the correct value is because the R script can
> recursively call itself, e.g.
> 
> R CMD Sweave foo.Rnw
> 
> will call two instances of the R shell script, and in the second call
> R_HOME is already set by the first call.

Thanks for the explanation.

Spot I think the decision is up to you but I think we should not break
R :-)

Martyn, are you in contact with the guys from rJava ?
Would it be possible to ask then to make JRI asking R for the R_HOME
instead of asking an shell variable ?

Best regards,

Pierre