Update MS Windows PATH variable based on a R script

This is a very very very late follow up, but I remember asking this question
and just stumbled across an answer by Yihui. Check his file
'add-R-path-win.R' script which you can find at
https://github.com/yihui/lyx/blob/master/README.md

Very cool, thanks Yihui.

Regards,
Janko


On 29.06.2011 20:58, Duncan Murdoch wrote:

On 29/06/2011 2:24 PM, Janko Thyson wrote:

Dear list,

this is not directly an R question, but it is somewhat related to R
aspects, so I hope it's okay to post it here:

I'd like to update my windows PATH based on a script routine in order to
make sure that crucial components are contained. Much like what happens
at the installation of Rtools (if desired). Now, can you do that from
within R or do I need some sort of windows batch file or something like
AutoIt script (http://www.autoitscript.com/site/autoit/)? If so, what
would I need to put in there?

You need to set the registry entry if you want a persistent change to the
PATH. ?Sys.setenv just modifies R's copy of the PATH. ?Child processes will
see the modifications, but they don't last beyond the R session.

You'll have to check MS docs to find which registry entry to mess with.
?Alternatively, if you feel lucky, just use Control Panel to set some
strange path, then see where your change showed up using regedit.

R doesn't have a built-in function to write to the registry, but there are
various utilities available outside of R to do it.

Duncan Murdoch

Here's what I tried in R:

unlist(strsplit(Sys.getenv("PATH"), ";"))
PATH.0<- Sys.getenv("PATH")
PATH.1<- paste(PATH.0, "C:\\blabla\bin")
Sys.setenv("PATH"=PATH.1)
unlist(strsplit(Sys.getenv("PATH"), ";"))

The changes seem to be reflected, but when I check my PATH the new entry
isn't there. I guess there is no actual "feedback" to Windows system
environment variable and that's exactly what I would like to accomplish

Thanks a lot for any advice,
Janko