Rscript                package:utils                R Documentation

Scripting Front-End for R

Description:

     This is an alternative front end for use in '#!' scripts and other
     scripting applications.

Usage:

     Rscript [options] [-e expression] file [args]

Arguments:

 options: A list of options beginning with '--'.  These can be any of
          the options of the standard R front-end, and also those
          described in the details.

expression: a R expression.

    file: The name of a file containing R commands.  '-' indicates
          'stdin'.

    args: Arguments to be passed to the script in 'file'.

Details:

     'Rscript --help' gives details of usage, and 'Rscript --version'
     gives the version of 'Rscript'.

     Other invocations invoke the R front-end with selected options. 
     This front-end is convenient for writing '#!' scripts since it is
     an executable and takes 'file' directly as an argument.  Options
     '--slave --no-restore' are always supplied: these imply
     '--no-save'.

     _Either_ one or more '-e' options or 'file' should be supplied. 
     When using '-e' options be aware of the quoting rules in the shell
     used: see the examples.

     Additional options accepted (before 'file' or 'args') are

     '--verbose' gives details of what 'Rscript' is doing.  Also passed
          on to R.

     '--default-packages=list' where 'list' is a comma-separated list
          of package names or 'NULL'.  Sets the environment variable
          'R_DEFAULT_PACKAGES' which determines the packages loaded on
          startup.  The default for 'Rscript' omits 'methods' as it
          takes about 60% of the startup time.


     Normally the version of R is determined at installation, but this
     can be overridden by setting the environment variable 'RHOME'.

     'stdin()' refers to the input file, and 'file("stdin")' to the
     'stdin' file stream of the process.

Note:

     'Rscript' is only supported on systems with the 'execv' system
     call.

Examples:

     ## Not run: 
     Rscript -e 'date()' -e 'format(Sys.time(), "%a %b %d %X %Y")'

     ## example #! script for a Unix-alike

     #! /path/to/Rscript --vanilla --default-packages=utils
     args <- commandArgs(TRUE)
     res <- try(install.packages(args))
     if(inherits(res, "try-error")) q(status=1) else q()

     ## End(Not run)

