startup (version 0.9.0)

restart: Restarts R

Description

Restarts R by quitting the current R session and launching a new one.

Usage

restart(status = 0L, workdir = NULL, rcmd = NULL, args = NULL,
  envvars = NULL, as = c("current", "specified", "R CMD build",
  "R CMD check", "R CMD INSTALL"), debug = NA)

Arguments

status

An integer specifying the exit code of the current R session.

workdir

The working directory where the new R session should be launched from. If NULL, then the working directory that was in place when the startup package was first loaded. If using startup::startup() in an .Rprofile startup file, then this is likely to record the directory from which R itself was launched from.

rcmd

A character string specifying the command for launching R. The default is the same as used to launch the current R session, i.e. commandArgs()[1].

args

A character vector specifying zero or more command-line arguments to be appended to the system call of rcmd.

envvars

A named character vector of environment variables to be set when calling R.

as

A character string specifying a predefined setups of rcmd, args, and envvars. For details, see below.

debug

If TRUE, debug messages are outputted, otherwise not.

Predefined setups

Argument as may take the following values:

"current":

(Default) A setup that emulates the setup of the current R session as far as possible by relaunching R with the same command-line call (= base::commandArgs()).

"specified":

According to rcmd, args, and envvars.

"R CMD build":

A setup that emulates R CMD build as far as possible.

"R CMD check":

A setup that emulates R CMD check as far as possible, which happens to be identical to the "R CMD build" setup.

"R CMD INSTALL":

A setup that emulates R CMD INSTALL as far as possible.

If specified, command-line arguments in args and environment variables in envvars are appended accordingly.

Known limitations

It is not possible to restart an R session in RStudio using this function. Note, RStudio provides .rs.restartR() which will indeed restart the current R session. However, it does not let you control how R is restarted, e.g. with what command-line options and what environment variables. Furthermore, the new R session will have the same set of packages loaded as before, the same variables in the global environment, and so on.

Examples

# NOT RUN {
  ## Relaunch R with debugging of startup::startup() enabled
  startup::restart(envvars = c(R_STARTUP_DEBUG = TRUE))

  ## Mimic 'R CMD build' and 'R CMD check'
  startup::restart(as = "R CMD build")
  startup::restart(as = "R CMD check")
  ## ... which are both short for
  startup::restart(args = c("--no-restore"),
                   envvars = c(R_DEFAULT_PACKAGES="", LC_COLLATE="C"))
# }
# NOT RUN {
# }