Updated some of the callbacks in callback.lua.

Update get.lua to use the new callbacks.
The old "code" module is now the "mime" module.
Updated all modules that depended on it.
Updated url.lua to use the new namespace scheme, and moved the
    escape and unescape functions that used to be in the code.lua module
    to it, since these are specific to urls.
Updated the callback entries in the manual.

etc/get.lua

@@ -42,8 +42,8 @@ function nicesize(b)
 end
 
 -- returns a string with the current state of the download
-function gauge(got, dt, size)
-	local rate = got / dt
+function gauge(got, delta, size)
+	local rate = got / delta
 	if size and size >= 1 then
 		return string.format("%s received, %s/s throughput, " ..
 			"%.0f%% done, %s remaining", 
@@ -55,53 +55,56 @@ function gauge(got, dt, size)
 		return string.format("%s received, %s/s throughput, %s elapsed", 
 			nicesize(got), 
 			nicesize(rate),
-			nicetime(dt))
+			nicetime(delta))
 	end
 end
 
 -- creates a new instance of a receive_cb that saves to disk
 -- kind of copied from luasocket's manual callback examples
-function receive2disk(file, size)
-	local aux = {
-        start = socket.time(),
-        got = 0,
-        file = io.open(file, "wb"),
-		size = size
-    }
-    local receive_cb = function(chunk, err)
-        local dt = socket.time() - aux.start  -- elapsed time since start
-        if not chunk or chunk == "" then
-			io.write("\n")
-            aux.file:close()
-            return
+function stats(size)
+    local start = socket.time()
+    local got = 0
+    return function(chunk)
+        -- elapsed time since start
+        local delta = socket.time() - start 
+        if chunk then 
+            -- total bytes received
+            got = got + string.len(chunk)    
+            -- not enough time for estimate
+            if delta > 0.1 then 
+                io.stderr:write("\r", gauge(got, delta, size)) 
+                io.stderr:flush()
+            end
+            return chunk
+        else 
+            -- close up
+            io.stderr:write("\n") 
+            return ""
         end
-        aux.file:write(chunk)
-        aux.got = aux.got + string.len(chunk)  -- total bytes received
-        if dt < 0.1 then return 1 end          -- not enough time for estimate
-		io.write("\r", gauge(aux.got, dt, aux.size))
-        return 1
     end
-	return receive_cb
 end
 
 -- downloads a file using the ftp protocol
 function getbyftp(url, file)
+    local save = socket.callback.receive.file(file or io.stdout)
+    if file then 
+        save = socket.callback.receive.chain(stats(gethttpsize(url)), save)
+    end
     local err = socket.ftp.get_cb {
         url = url,
-        content_cb = receive2disk(file),
+        content_cb = save,
         type = "i"
     }
-	print()
 	if err then print(err) end
 end
 
 -- downloads a file using the http protocol
-function getbyhttp(url, file, size)
-    local response = socket.http.request_cb(
-        {url = url},
-		{body_cb = receive2disk(file, size)}
-    )
-	print()
+function getbyhttp(url, file)
+    local save = socket.callback.receive.file(file or io.stdout)
+    if file then 
+        save = socket.callback.receive.chain(stats(gethttpsize(url)), save)
+    end
+    local response = socket.http.request_cb({url = url}, {body_cb = save})
 	if response.code ~= 200 then print(response.status or response.error) end
 end
 
@@ -116,26 +119,22 @@ function gethttpsize(url)
 	end
 end
 
--- determines the scheme and the file name of a given url
-function getschemeandname(url, name)
+-- determines the scheme 
+function getscheme(url)
 	-- this is an heuristic to solve a common invalid url poblem
 	if not string.find(url, "//") then url = "//" .. url end
 	local parsed = socket.url.parse(url, {scheme = "http"})
-	if name then return parsed.scheme, name end
-	local segment = socket.url.parse_path(parsed.path)
-	name = segment[table.getn(segment)]
-	if segment.is_directory then name = nil end
-	return parsed.scheme, name
+	return parsed.scheme
 end
 
 -- gets a file either by http or ftp, saving as <name>
 function get(url, name)
-	local scheme
-    scheme, name = getschemeandname(url, name)
-	if not name then print("unknown file name")
-	elseif scheme == "ftp" then getbyftp(url, name)
-	elseif scheme == "http" then getbyhttp(url, name, gethttpsize(url)) 
+    local fout = name and io.open(name, "wb")
+	local scheme = getscheme(url)
+	if scheme == "ftp" then getbyftp(url, fout)
+	elseif scheme == "http" then getbyhttp(url, fout)
 	else print("unknown scheme" .. scheme) end
+    if name then fout:close() end
 end
 
 -- main program