The function returns a data frame with one row for each downloaded file and
the following columns:
success if the HTTP request was successfully performed, regardless of the
response status code. This is FALSE in case of a network error, or in case
you tried to resume from a server that did not support this. A value of NA
means the download was interrupted while in progress.
status_code the HTTP status code from the request. A successful download is
usually 200 for full requests or 206 for resumed requests. Anything else
could indicate that the downloaded file contains an error page instead of the
requested content.
resumefrom the file size before the request, in case a download was resumed.
url final url (after redirects) of the request.
destfile downloaded file on disk.
error if success == FALSE this column contains an error message.
type the Content-Type response header value.
modified the Last-Modified response header value.
time total elapsed download time for this file in seconds.
headers vector with http response headers for the request.