%09%09<gopher+_string>





 
RFC 1738            Uniform Resource Locators (URL)        December 1994


   If : is omitted, the port defaults to 70.   is a
   single-character field to denote the Gopher type of the resource to
   which the URL refers. The entire <gopher-path> may also be empty, in
   which case the delimiting "/" is also optional and the 
   defaults to "1".

    is the Gopher selector string.  In the Gopher protocol,
   Gopher selector strings are a sequence of octets which may contain
   any octets except 09 hexadecimal (US-ASCII HT or tab) 0A hexadecimal
   (US-ASCII character LF), and 0D (US-ASCII character CR).

   Gopher clients specify which item to retrieve by sending the Gopher
   selector string to a Gopher server.

   Within the <gopher-path>, no characters are reserved.

   Note that some Gopher  strings begin with a copy of the
    character, in which case that character will occur twice
   consecutively. The Gopher selector string may be an empty string;
   this is how Gopher clients refer to the top-level directory on a
   Gopher server.

3.4.2 Specifying URLs for Gopher Search Engines

   If the URL refers to a search to be submitted to a Gopher search
   engine, the selector is followed by an encoded tab (%09) and the
   search string. To submit a search to a Gopher search engine, the
   Gopher client sends the  string (after decoding), a tab,
   and the search string to the Gopher server.

3.4.3 URL syntax for Gopher+ items

   URLs for Gopher+ items have a second encoded tab (%09) and a Gopher+
   string. Note that in this case, the %09 string must be
   supplied, although the  element may be the empty string.

   The <gopher+_string> is used to represent information required for
   retrieval of the Gopher+ item. Gopher+ items may have alternate
   views, arbitrary sets of attributes, and may have electronic forms
   associated with them.

   To retrieve the data associated with a Gopher+ URL, a client will
   connect to the server and send the Gopher selector, followed by a tab
   and the search string (which may be empty), followed by a tab and the
   Gopher+ commands.







 
RFC 1738            Uniform Resource Locators (URL)        December 1994


3.4.4 Default Gopher+ data representation

   When a Gopher server returns a directory listing to a client, the
   Gopher+ items are tagged with either a "+" (denoting Gopher+ items)
   or a "?" (denoting Gopher+ items which have a +ASK form associated
   with them). A Gopher URL with a Gopher+ string consisting of only a
   "+" refers to the default view (data representation) of the item
   while a Gopher+ string containing only a "?" refer to an item with a
   Gopher electronic form associated with it.

3.4.5 Gopher+ items with electronic forms

   Gopher+ items which have a +ASK associated with them (i.e. Gopher+
   items tagged with a "?") require the client to fetch the item's +ASK
   attribute to get the form definition, and then ask the user to fill
   out the form and return the user's responses along with the selector
   string to retrieve the item.  Gopher+ clients know how to do this but
   depend on the "?" tag in the Gopher+ item description to know when to
   handle this case. The "?" is used in the Gopher+ string to be
   consistent with Gopher+ protocol's use of this symbol.

3.4.6 Gopher+ item attribute collections

   To refer to the Gopher+ attributes of an item, the Gopher URL's
   Gopher+ string consists of "!" or "$". "!" refers to the all of a
   Gopher+ item's attributes. "$" refers to all the item attributes for
   all items in a Gopher directory.

3.4.7 Referring to specific Gopher+ attributes

   To refer to specific attributes, the URL's gopher+_string is
   "!<attribute_name>" or "$<attribute_name>". For example, to refer to
   the attribute containing the abstract of an item, the gopher+_string
   would be "!+ABSTRACT".