R - Environment variable

Get

• Get Sys.getenv

# All
Sys.getenv()

# One
Sys.getenv("TMP")

# Several
Sys.getenv(c("R_HOME", "R_PAPERSIZE", "R_PRINTCMD", "HOST"))

Set

Sys.setenv(HOME="/usr/bla")

Unset

Sys.unsetenv("HOME")