download_file: Try various methods to download a file

In xfun: Supporting Functions for Packages Maintained by 'Yihui Xie'

Try various methods to download a file

Description

Try all possible methods in download.file() (e.g., libcurl, curl, wget, and wininet) and see if any method can succeed. The reason to enumerate all methods is that sometimes the default method does not work, e.g., https://stat.ethz.ch/pipermail/r-devel/2016-June/072852.html.

Usage

download_file(
  url,
  output = url_filename(url),
  ...,
  .error = "No download method works (auto/wininet/wget/curl/lynx)"
)

Arguments

url	The URL of the file.
output	Path to the output file. By default, it is determined by url_filename().
...	Other arguments to be passed to download.file() (except method).
.error	An error message to signal when the download fails.

Value

The integer code 0 for success, or an error if none of the methods work.

Note

To allow downloading large files, the timeout option in options() will be temporarily set to one hour (3600 seconds) inside this function when this option has the default value of 60 seconds. If you want a different timeout value, you may set it via options(timeout = N), where N is the number of seconds (not 60).

xfun documentation built on Nov. 2, 2023, 6 p.m.