R devel - Apr 2005 - Feature request: report the url if 404 error occurs

Currently, the connection code does not include the URL in the warning
message when a 404 response is received:

myUrl = "http://www.r-project.org/ABadPage.html"
con = url(myUrl)
readLines(con)

  Error in readLines(con) : cannot open the connection
  In addition: Warning message:
  cannot open: HTTP status was '404 Not Found' 

Would it be possible (and desirable) to include the URL in the warning
message?  Here's an example:

Error in readLines(con) : cannot open the connection
In addition: Warning message:
cannot open 'http://www.r-project.org/ABadPage.html': HTTP status was
'404 Not Found'


+ seth

On Mon, 25 Apr 2005, Seth Falcon wrote:
> Currently, the connection code does not include the URL in the warning
> message when a 404 response is received:
>
> myUrl = "http://www.r-project.org/ABadPage.html"
> con = url(myUrl)
> readLines(con)
>
>  Error in readLines(con) : cannot open the connection
>  In addition: Warning message:
>  cannot open: HTTP status was '404 Not Found'
>
> Would it be possible (and desirable) to include the URL in the warning
> message?  Here's an example:
>
> Error in readLines(con) : cannot open the connection
> In addition: Warning message:
> cannot open 'http://www.r-project.org/ABadPage.html': HTTP status
was '404 Not Found'
It is part of `con':
> con
                              description
"http://www.r-project.org/ABadPage.html"
                                    class
                                    "url"
                                     mode
                                      "r"
                                     text
                                   "text"
                                   opened
                                 "closed"
                                 can read
                                    "yes"
                                can write
                                     "no"

Remember R is an interactive system: you just need to ask it for the 
information you want.

This would be tedious to add, but you could submit a patch (remember there 
are at least three places to look at in the internet code).

-- 
Brian D. Ripley,                  ripley@stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595