download.packages {utils} | R Documentation |
These functions can be used to automatically compare the version numbers of installed packages with the newest available version on the repositories and update outdated packages on the fly.
download.packages(pkgs, destdir, available = NULL, repos = getOption("repos"), contriburl = contrib.url(repos, type), method, type = getOption("pkgType"), ...)
pkgs |
character vector of the names of packages whose latest available versions should be downloaded from the repositories. |
destdir |
directory where downloaded packages are to be stored. |
available |
an object as returned by |
repos |
character vector, the base URL(s) of the repositories
to use, i.e., the URL of the CRAN master such as
|
contriburl |
URL(s) of the contrib sections of the
repositories. Use this argument only if your repository mirror is
incomplete, e.g., because you burned only the ‘contrib’ section on a
CD. Overrides argument |
method |
Download method, see |
type |
character string, indicate which type of packages: see
|
... |
additional arguments to be passed to |
download.packages
takes a list of package names and a
destination directory, downloads the newest versions and saves them in
destdir
. If the list of available packages is not given as
argument, it is obtained from repositories. If a repository is local,
i.e. the URL starts with "file:"
, then the packages are not
downloaded but used directly. Both "file:"
and
"file:///"
are allowed as prefixes to a file path. Use the
latter only for URLs: see url
for their interpretation.
(Other forms of file:// URLs are not supported.)
For download.packages
, type = "both"
looks at source
packages only.
A two-column matrix of names and destination file names of those packages successfully downloaded. If packages are not available or there is a problem with the download, suitable warnings are given.
available.packages
, contrib.url
.
The main use is by install.packages
.
See download.file
for how to handle proxies and
other options to monitor file transfers.
The ‘R Installation and Administration’ manual for how to set up a repository.