R: Downloads a file

downloadFile.character {R.utils} | R Documentation

## Downloads a file

### Description

Downloads a file.

### Usage

    ## S3 method for class 'character'
    downloadFile(url, filename=basename(url), path=NULL, skip=TRUE, overwrite=!skip, ...,
      username=NULL, password=NULL, binary=TRUE, dropEmpty=TRUE, verbose=FALSE)

### Arguments

`url` | A `character` string specifying the URL to be downloaded.
`filename, path` | (optional) `character` strings specifying the local filename and the path of the downloaded file.
`skip` | If `TRUE`, an already downloaded file is skipped.
`overwrite` | If `TRUE`, an already downloaded file is overwritten, otherwise an error is thrown.
`...` | Additional arguments passed to `download.file`.
`username, password` | `character` strings specifying the username and password for authenticated downloads. The alternative is to specify these via the URL.
`binary` | If `TRUE`, the file is downloaded exactly "as is", that is, byte by byte (recommended).
`dropEmpty` | If `TRUE` and the downloaded file is empty, the file is ignored and `NULL` is returned.
`verbose` | A `logical`, `integer`, or a `Verbose` object.

### Details

Currently arguments `username` and `password` are only used for downloads via URL protocol 'https'. The 'https' protocol requires that either of 'curl' or 'wget' are available on the system.

### Value

Returns the local pathname to the downloaded filename, or `NULL` if no file was downloaded.

### Author(s)

Henrik Bengtsson

### See Also

Internally `download.file` is used. That function may generate an empty file if the URL is not available.

### Examples

    ## Not run:
     pathname <- downloadFile("http://www.r-project.org/index.html", path="www.r-project.org/")
     print(pathname)

    ## End(Not run)

[Package R.utils version 2.7.0 Index]