The 'Head' method

Argument: Character Vector
Result: 3-element Nested Vector

Valid for: HTTPClient

The Head method retrieves information about a page or other file from a web-server. The argument is a character vector which is the URL (e.g. 'http://www.microapl.co.uk/apl/index.html').

The result is a three element vector.

The first element is the HTTP return code, which is an integer scalar. A number in the range 200 to 299 indicates success. A number in the range 400 to 499 indicates an error, such as 404 meaning 'page not found'.

The second element is a character vector indicating the MIME type of the returned data, such as 'text/plain'.

The third element is a character vector containing the HTTP header associated with the page.

For example:

     (errcode mimetype text) ← HTTP.Head 'http://www.microapl.co.uk/apl'
      errcode
200
      mimetype
text/html
      text
Server: Zeus/4.2
Date: Wed, 09 Feb 2005 12:19:41 GMT
Content-Type: text/html
Content-Length: 10437
Accept-Ranges: bytes
Last-Modified: Thu, 07 Oct 2004 11:35:34 GMT