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/etc/R/Renviron

The purpose of the Renviron file is to set environment variables.

It might contain something like

LC_COLLATE  = "English_United States.1252"
LC_CTYPE    = "English_United States.1252"
LC_MONETARY = "English_United States.1252"
LC_NUMERIC  = "English_United States.1252"
LC_TIME     = "English_United States.1252"

In an R session, it can be edited or created using file.edit():

renv = path.expand(file.path('~', '.Renviron'));
file.edit(renv);

/etc/R/Renviron

See also