EnvVar {base} | R Documentation |
Details of some of the environment variables which affect an R session.
It is impossible to list all the environment variables which can affect an R session: some affect the OS system functions which R uses, and others will affect add-on packages. But here are notes on some of the more important ones. Those that set the defaults for options are consulted only at startup (as are some of the others).
HOME
:The user's ‘home’ directory.
LANGUAGE
:Optional. The language(s) to be used for message translations. This is consulted when needed.
LC_ALL
:(etc) Optional. Use to set various aspects of
the locale – see Sys.getlocale
. Consulted at startup.
R_BATCH
:Optional – set in a batch session.
R_BROWSER
:The path to the default browser. Used to
set the default value of options("browser")
.
R_COMPLETION
:Optional. If set to FALSE
,
comand-line completion is not used. (Not used by Mac OS GUI.)
R_DEFAULT_PACKAGES
:A comma-separated list of packages
which are to be loaded in every session. See options
.
R_DOC_DIR
:The location of the R ‘doc’ directory. Set by R.
R_DVIPSCMD
:The path to dvips
. Defaults to
the value of DVIPS, and if that is unset to a value
determined when R was built.
Used by R CMD Rd2dvi
, and at startup to set the default for
options("latexcmd")
, used by
help(offline = TRUE
.
R_ENVIRON
:Optional. The path to the site environment file: see Startup. Consulted at startup.
R_GSCMD
:Optional. The path to GhostScript, used by
dev2bitmap
.
R_HISTFILE
:Optional. The path of the history file: see Startup. Consulted at startup and when the history is saved.
R_HISTSIZE
:Optional. The maximum size of the history
file, in lines. Exactly how this is used depends on the
interface.
For the readline
command-line interface it takes effect
when the history is saved (by savehistory
or at the
end of a session).
R_HOME
:The top-level directory of the R
installation: see R.home
. Set by R.
R_INCLUDE_DIR
:The location of the R ‘include’ directory. Set by R.
R_LATEXCMD
:The path to latex
. Defaults to
the value of LATEX, and if that is unset to a value
determined when R was built.
Used by R CMD Rd2dvi
, and at startup to set the default for
options("latexcmd")
, used by
help(offline = TRUE
.
R_LIBS
:Optional. Used for initial setting of
.libPaths
.
R_LIBS_SITE
:Optional. Used for initial setting of
.libPaths
.
R_LIBS_USER
:Optional. Used for initial setting of
.libPaths
.
R_MAKEINDEXCMD
:The path to makeindex
. Defaults
at startup to the value of MAKEINDEX, and if that is unset
to a value determined when R was built. Used by R CMD Rd2dvi
.
R_PAPERSIZE
:Optional. Use to set the default for
options("papersize")
, e.g. used by
pdf
, postscript
and
help(offline = TRUE)
.
R_PDFLATEXCMD
:The path to pdflatex
. Defaults
at startup to the value of PDFLATEX
, and if that is unset
to a value determined when R was built. Used by R CMD Rd2dvi
.
R_PDFVIEWER
:The path to the default PDF viewer. Used
by R CMD Rd2dvi
.
R_PLATFORM
:The platform – a string of the form
cpu-vendor-os
, see R.Version
.
R_PROFILE
:Optional. The path to the site profile file: see Startup. Consulted at startup.
R_RD4DVI
:Options for latex
processing of
Rd
files. Used by R CMD Rd2dvi
and
help(offline = TRUE)
.
R_RD4PDF
:Options for pdflatex
processing of
Rd
files. Used by R CMD Rd2dvi
.
R_SHARE_DIR
:The location of the R ‘share’ directory. Set by R.
R_TEXI2DVICMD
:The path to texi2dvi
. Defaults
to the value of TEXI2DVI, and if that is unset to a value
determined when R was built.
Consulted at startup to set the default for
options("texi2dvi")
, used by
texi2dvi
in package tools.
R_UNZIPCMD
:The path to unzip
. Sets the default
value for options("unzip")
.
R_ZIPCMD
:The path to zip
.
TMPDIR
, TMP
, TEMP
:Consulted (in that
order) when setting the temporary directory. See
tempdir
.
TZ
:Optional. The current timezone. See
Sys.timezone
for the system-specific
formats. Consulted as needed.
no_proxy
, http_proxy
, ftp_proxy
:(and more). Optional. Settings for download.file
:
see its help for further details.
Some variables set on Unix-alikes, and not (in general) on Windows.
DISPLAY
:Optional: used by X11
, Tk (in
package tcltk), the data editor and various packages.
EDITOR
:The path to the default editor.
PAGER
:The path to the default pager.
R_PRINTCMD
:Sets the default for
options("printcmd")
, which sets the default print
command to be used by postscript
.
Sys.getenv
and Sys.setenv
to read and set
environmental variables in an R session.