update.packages             package:base             R Documentation

Download Packages from CRAN

Description:

     These functions can be used to automatically compare the version
     numbers of installed packages with the newest available version on
     CRAN and update outdated packages on the fly.

Usage:

     update.packages(lib.loc = NULL, CRAN = getOption("CRAN"),
                     contriburl = contrib.url(CRAN),
                     method, instlib = NULL,
                     ask=TRUE, available=NULL, destdir=NULL)

     installed.packages(lib.loc = NULL)
     CRAN.packages(CRAN = getOption("CRAN"), method = "auto",
                   contriburl = contrib.url(CRAN))
     old.packages(lib.loc = NULL, CRAN = getOption("CRAN"),
                  contriburl = contrib.url(CRAN),
                  method, available = NULL)

     download.packages(pkgs, destdir, available = NULL,
                       CRAN = getOption("CRAN"), 
                       contriburl = contrib.url(CRAN), method = "auto")
     install.packages(pkgs, lib, CRAN = getOption("CRAN"),
                      contriburl = contrib.url(CRAN),
                      method, available = NULL, destdir = NULL)

Arguments:

 lib.loc: A character vector describing the location of R library trees
          to search through (and update packages therein).

    CRAN: The base URL of the CRAN mirror to use, i.e., the URL of a
          CRAN root such as `"http://cran.r-project.org"' (the default)
          or its Statlib mirror, `"http://lib.stat.cmu.edu/R/CRAN"'.

contriburl: URL of the contrib section of CRAN. Use this argument only
          if your CRAN mirror is incomplete, e.g., because you burned
          only the contrib section on a CD.  Overrides argument `CRAN'.

  method: Download method, see `download.file'.

    pkgs: A character vector of the short names of packages whose
          current versions should be downloaded from `CRAN'.

 destdir: Directory where downloaded packages are stored.

available: List of packages available at CRAN as returned by
          `CRAN.packages'.

lib,instlib: A character string giving the library directory where to
          install the packages.

     ask: If `TRUE', ask before packages are actually downloaded and
          installed.

Details:

     `installed.packages' scans the `DESCRIPTION' files of each package
     found along `lib.loc' and returns a list of package names, library
     paths and version numbers.  `CRAN.packages' returns a similar
     list, but corresponding to packages currently available in the
     contrib section of CRAN, the comprehensive R archive network.  The
     current list of packages is downloaded over the internet (or
     copied from a local CRAN mirror). Both functions use `read.dcf'
     for parsing the description files. `old.packages' compares the two
     lists and reports installed packages that have newer versions on
     CRAN.

     `download.packages' takes a list of package names and a
     destination directory, downloads the newest versions of the
     package sources and saves the in `destdir'.  If the list of
     available packages is not given as argument, it is also directly
     obtained from CRAN.  If CRAN is local, i.e., the URL starts with
     `"file:"', then the packages are not downloaded but used directly.

     The main function of the bundle is `update.packages'.  First a
     list of all packages found in `lib.loc' is created and compared
     with the packages available on CRAN.  Outdated packages are
     reported and for each outdated package the user can specify if it
     should be automatically updated. If so, the package sources are
     downloaded from CRAN and installed in the respective library path
     (or `instlib' if specified) using the R `INSTALL' mechanism.

     `install.packages' can be used to install new packages, it takes a
     vector of package names and a destination library, downloads the
     packages from CRAN and installs them. If the library is omitted it
     defaults to the first directory in `.libPaths()', with a warning.

     For `install.packages' and `update.packages', `destdir' is the
     directory to which packages will be downloaded. If it is `NULL'
     (the default) a temporary directory is used, and the user will be
     given the option of deleting the temporary files once the packages
     are installed.

See Also:

     `INSTALL', `REMOVE', `library', `.packages', `read.dcf',
     `download.file'

