Hi again,
Oops! I have to take back that last message. I’m working on two OS and got them confused. R updated to 3.5.0 on my iMac running OS X 10.11.6 and RStudio recognises and uses it on that machine, but not on my Linux laptop running Mint 18.3 — the latter is the problem.
My apologies! I have a lot of things on the go right now.
I downloaded 3.5.0 for Linux Ubuntu (Mint 18 is based on 16.04) and opened it into a directory in /home, then compiled it from that using the enable-R-shlib option. It installed into /usr/local/bin, so I added the export RSTUDIO_WHICH_R=/usr/local/bin/R line to ~/.profile as indicated in https://support.rstudio.com/hc/en-us/articles/200486138-Changing-R-versions-for-RStudio-desktop.
However, Although RStudio can be invoked both from the Applications Menu and the command line, neither will use R 3.5.0 but opens with R 3.4.4.
Sys.getenv("RSTUDIO_WHICH_R") returns /usr/bin/R, which is the location of 3.4.4, so I presume this is overriding the setting in ~.profile.
That seems to be the problem — can I change that?
Stuart