| Sys.getenv {base} | R Documentation |
Sys.getenv obtains the values of the environment variables.
Sys.getenv(x = NULL, unset = "", names = NA)
x |
a character vector, or |
unset |
a character string. |
names |
logical: should the result be named? If |
Both arguments will be coerced to character if necessary.
Setting unset = NA will enable unset variables and those set to
the value "" to be distinguished, if the OS does. POSIX
requires the OS to distinguish, and all known current R platforms do.
A vector of the same length as x, with (if names ==
TRUE) the variable names as its names attribute. Each element
holds the value of the environment variable named by the corresponding
component of x (or the value of unset if no environment
variable with that name was found).
On most platforms Sys.getenv() will return a named vector
giving the values of all the environment variables, sorted in the
current locale. It may be confused by names containing = which
some platforms allow but POSIX does not. (Windows is such a platform:
there names including = are truncated just before the first
=.)
Argument names was introduced in R 2.13.0 to avoid needing the
common use of as.vector(Sys.getenv()).
Sys.setenv,
Sys.getlocale for the locale in use,
getwd for the working directory.
The help for ‘environment variables’ lists many of the environment variables used by R.
## whether HOST is set will be shell-dependent e.g. Solaris' csh does not.
Sys.getenv(c("R_HOME", "R_PAPERSIZE", "R_PRINTCMD", "HOST"))
names(s <- Sys.getenv()) # all settings (the values could be very long)
## Language and Locale settings -- but rather use Sys.getlocale()
s[grep("^L(C|ANG)", names(s))]