R: Download File from the Internet

download.file {base} | R Documentation

## Download File from the Internet

### Description

This function can be used to download a file from the Internet.

### Usage

    download.file(url, destfile, method, quiet = FALSE, mode="w",
                  cacheOK = TRUE)

### Arguments

`url` | A character string naming the URL of a resource to be downloaded.
`destfile` | A character string with the name where the downloaded file is saved. Tilde-expansion is performed.
`method` | Method to be used for downloading files. Currently download methods `"internal"`, `"wget"` and `"lynx"` are available. The default is to choose the first of these which `"internal"`. The method can also be set through the option `"download.file.method"`: see `options()`.
`quiet` | If `TRUE`, suppress status messages (if any).
`mode` | character. The mode with which to write the file. Useful values are `"w"`, `"wb"` (binary), `"a"` (append) and `"ab"`. Only used for the `"internal"` method.
`cacheOK` | logical. Is a server-side cached value acceptable? Implemented for the `"internal"` and `"wget"` methods.

### Details

The function `download.file` can be used to download a single file as described by `url` from the internet and store it in `destfile`. The `url` must start with a scheme such as `"http://"`, `"ftp://"` or `"file://"`.

`cacheOK = FALSE` is useful for `"http://"` URLs, and will attempt to get a copy directly from the site rather than from an intermediate cache. (Not all platforms support it.) It is used by `CRAN.packages`.

The remaining details apply to method `"internal"` only.

The timeout for many parts of the transder can be set by the option `timeout` which defaults to 60 seconds.

The level of detail provided during transfer can be set by the `quiet` argument and the `internet.info` option. The details depend on the platform and scheme, but setting `internet.info` to 0 gives all available details, including all server responses. Using 2 (the default) gives only serious messages, and 3 or more suppresses all messages.

Proxies can be specified via environment variables. Setting `"no_proxy"` stops any proxy being tried. Otherwise the setting of `"http_proxy"` or `"ftp_proxy"` (or failing that, the all upper-case version) is consulted and if non-empty used as a proxy site. For FTP transfers, the username and password on the proxy can be specified by `"ftp_proxy_user"` and `"ftp_proxy_password"`.

Method `"wget"` can be used with proxy firewalls which require user/password authentication if proper values are stored in the configuration file for `wget`.

### Note

Methods `"wget"` and `"lynx"` are for historical compatibility. They will block all other activity on the R process.

For methods `"wget"` and `"lynx"` a system call is made to the tool given by `method`, and the respective program must be installed on your system and be in the search path for executables.

### See Also

`options` to set the `timeout` and `internet.info` options.

`url` for a finer-grained way to read data from URLs.

`url.show`, `CRAN.packages`, `download.packages` for applications

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