R: Select a CRAN Mirror

chooseCRANmirror {utils}

R Documentation

Select a CRAN Mirror

Description

Interact with the user to choose a CRAN mirror.

Usage

chooseCRANmirror(graphics = getOption("menu.graphics"), ind = NULL,
                 useHTTPS = getOption("useHTTPS", TRUE),
                 local.only = FALSE)

getCRANmirrors(all = FALSE, local.only = FALSE)

Arguments

`graphics`	Logical. If true, use a graphical list: on Windows or the macOS GUI use a list box, and on a Unix-alike use a Tk widget if package tcltk and an X server are available. Otherwise use a text `menu`.
`ind`	Optional numeric value giving which entry to select.
`useHTTPS`	Whether to prefer secure mirrors.
`all`	Logical, get all known mirrors or only the ones flagged as OK.
`local.only`	Logical, try to get most recent list from the CRAN master or use file on local disk only.

Details

A list of mirrors is stored in file ‘R_HOME/doc/CRAN_mirrors.csv’, but first an on-line list of current mirrors is consulted, and the file copy used only if the on-line list is inaccessible.

This function is called by a Windows GUI menu item and by contrib.url if it finds the initial dummy value of options("repos").

The useHTTPS argument defaults to TRUE. With useHTTPS = TRUE, HTTPS mirrors with mirroring over ssh will be offered in preference to other mirrors (which are listed in a sub-menu). If it is set to FALSE, no secure mirrors will be offered. Choosing a secure mirror provides some guarantees on the identity of the site chosen and so is recommended. (All R builds support downloading from HTTPS sites.)

ind chooses a row in the list of current mirrors, by number. It is best used with local.only = TRUE and row numbers in ‘R_HOME/doc/CRAN_mirrors.csv’.

Value

None for chooseCRANmirror(), this function is invoked for its side effect of updating options("repos").