Revive comment section from older version.

scheme/httpd/handlers.scm

@@ -1,4 +1,36 @@
-;; Request-handlers for scheme web server
+;;; http server in the Scheme Shell	-*- Scheme -*-
+
+;;; This file is part of the Scheme Untergrund Networking package.
+
+;;; Copyright (c) 1995 by Olin Shivers.
+;;; Copyright (c) 1996-2002 by Mike Sperber.
+;;; Copyright (c) 2002 by Andreas Bernauer.
+;;; For copyright information, see the file COPYING which comes with
+;;; the distribution.
+
+;;; Path handlers
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;; Path handlers are the guys that actually perform the requested operation
+;;; on the URL. The handler interface is 
+;;;     (handler path-list request)
+;;; The path-list is a URL path list that is a suffix of REQUEST's url's
+;;; path-list. Path handlers can decide how to handle an operation by
+;;; recursively keying off of the elements in path-list. 
+;;; 
+;;; The object-oriented view:
+;;; One way to look at this is to think of the request's METHOD as a
+;;; generic operation on the URL. Recursive path handlers do method 
+;;; lookup to determine how to implement a given operation on a particular
+;;; path.
+;;;
+;;; The REQUEST is a request record, as defined in httpd-core.scm, containing
+;;; the details of the client request. However, path handlers should *not*
+;;; read the request entity from, or write the reply to the request's socket.
+;;; Path-handler I/O should be done on the current i/o ports: if the handler
+;;; needs to read an entity, it should read it from (CURRENT-INPUT-PORT); when
+;;; the handler wishes to write a reply, it should write it to 
+;;; (CURRENT-OUTPUT-PORT). This makes it easy for the procedure that called
+;;; the handler to establish I/O indirections or filters if it so desires.
 
 ;; general request-handler-combinator:
 ;; predicate: path x request --> boolean