How do I correctly terminate an R session?
Table of Contents
Quit
When you run an R job, you should properly quit the job when you're done, by typing "q()" at the R prompt, and responding to the query about "Save workspace image?" appropriately. DO NOT log off without terminating your R job/session, and you should not kill a window with a running R process unless you follow one of the suggestions below.
Batch
If you want your R job to keep running after you log out, the best way to run R is through the BATCH command, i.e. run a command like this one at the UNIX prompt:
R CMD BATCH cmds.r output.txt &
where "cmds.r" is a file containing the R commands that you wish to run, and output.txt is the file where R will write its output. Type "help(BATCH)" from inside of R for more information. You can use this technique even if you don't think you'll be logging off before your job is done to make sure that R will terminate properly.
Explicit Invocation
If you don't want to worry about shutting down your interactive R session, you MUST use either the "-save" or the "-no-save" option. The reason that this is important is that if you log off or close a window while an interactive job is running, R will fall into an infinite loop at the end of your program, trying to ask you whether or not to save the data space. Using one of the options mentioned above will prevent this problem, as R will know the disposition of your data space before the program is completed. In other words, instead of just typing "R" at the UNIX prompt, type
R --save
or
R --no-save