Reload R package with compiled extensions

Is it possible to reload an R package with native extensions in an R session? I am developing Rliblinear, which uses several C functions. If I make a change to R code in the package, I can just reinstall and reload;

$ R CMD build R开发者_运维技巧liblinear
$ R CMD INSTALL Rliblinear

and then in an R shell;

> detach("package:Rliblinear", unload=TRUE)
> library(Rliblinear)

However, the C functions are not affected unless I restart the R interpreter. Is there a way I can force the interpreter to reload the shared object, Rliblinear.so?

This will list your loaded dynamic link libraries:

library.dynam()

and this will unload Rliblinear.* in the Rliblinear package.

library(Rliblinear)

# ... run package ...

detach("package:Rliblinear", unload = TRUE)
library.dynam.unload("Rliblinear", system.file(package = "Rliblinear"))

You can issue library.dynam() again just to check that its no longer listed.

I tend to do my tests on the command-line with littler to be sure I get a fresh R session. You can do this with Rscript too.

So my work flow would be

$ R CMD INSTALL Rliblinear/    ## alternatively, install from tarball
$ r -lRliblinear -e'someExpressionFromThePackage()'

which you can also wrap into a single line with && and/or precede with a clean step.

here is an extension to Mr G. Grothendieck answer, if embedded in "yourpackage" one can recompile it with one shot from R console:

reload <- function( path ){

   detach("package:yourpackage", unload = TRUE)
   library.dynam.unload("yourpackage", system.file(package = "yourpackage"))

   path <- paste( "--vanilla  CMD INSTALL ", path )

   system2( 'R', path  )
   require("yourpackage")
}

then from R:

yourpackage::reload( '/home/me/yourpackage' )