readme: update client usage

1 files changed, 12 insertions, 19 deletions

diff --git a/README.md b/README.md
index 28132d5..2abc857 100644
--- a/README.md
+++ b/README.md
@@ -7,11 +7,13 @@ A pure Ruby HTTP/2 implementation.
   * or latest Ruby 2.3.0-dev
 * OpenSSL 1.0.2 or newer (HTTP/2 requires ALPN)
 * Optional:
-  * [http_parser.rb gem](https://rubygems.org/gems/http_parser.rb) (HTTP/1.1 parser; if you use "http" URI scheme)
+  * [http_parser.rb gem](https://rubygems.org/gems/http_parser.rb) (HTTP/1.x parser; if you use "http" URI scheme)
   * [rack gem](https://rubygems.org/gems/rack) if you use Plum as Rack server.
 
 ## Usage
-### As a HTTP/2 client library
+### As a HTTP/2 (HTTP/1.x) client library
+If the server does't support HTTP/2, `Plum::Client` tries to use HTTP/1.x instead.
+
 ##### Sequential request
 ```ruby
 client = Plum::Client.start("http2.rhe.jp", 443)
@@ -25,31 +27,22 @@ client.close
 
 ##### Parallel request
 ```ruby
-client = Plum::Client.start("http2.rhe.jp", 443)
-res1 = client.get_async("/")
-res2 = client.post_async("/post", "data")
-client.wait # wait for response(s)
-client.close
-p res1.status # => 200
-```
-or
-```ruby
 res1 = res2 = nil
-Plum::Client.start("http2.rhe.jp", 443) { |client|
+Plum::Client.start("rhe.jp", http2_settings: { max_frame_size: 32768 }) { |client|
   res1 = client.get_async("/")
   res2 = client.post_async("/post", "data")
 } # wait for response(s) and close
 
-p res1.status # => 200
+p res1.status # => "200"
 ```
 
-##### Download large file
+##### Download a large file
 ```ruby
-Plum::Client.start("http2.rhe.jp", 443) { |client|
-  client.get_async("/large") do |res|
-    p res.status # => 200
+Plum::Client.start("http2.rhe.jp", hostname: "assets.rhe.jp") { |client|
+  client.get_async("/large") do |res| # called when received response headers
+    p res.status # => "200"
     File.open("/tmp/large.file", "wb") { |file|
-      res.each_chunk do |chunk|
+      res.on_chunk do |chunk|
         file << chunk
       end
     }
@@ -59,7 +52,7 @@ Plum::Client.start("http2.rhe.jp", 443) { |client|
 
 ### As a Rack-compatible server
 
-Most existing Rack-based applications (plum doesn't support Rack hijack API) should work without modification.
+Most existing Rack-based applications should work without modification.
 
 ```ruby
 # config.ru