constructor.rb in rio-0.3.8

- old
+ new

@@ -1,8 +1,8 @@
 #--
 # =============================================================================== 
-# Copyright (c) 2005, Christopher Kleckner
+# Copyright (c) 2005, 2006 Christopher Kleckner
 # All rights reserved
 #
 # This file is part of the Rio library for ruby.
 #
 # Rio is free software; you can redistribute it and/or modify
@@ -20,11 +20,11 @@
 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 # =============================================================================== 
 #++
 #
 # To create the documentation for Rio run the command
-#  rake rdoc
+#  ruby build_doc.rb
 # from the distribution directory. Then point your browser at the 'doc/rdoc' directory.
 #
 # Suggested Reading
 # * RIO::Doc::SYNOPSIS
 # * RIO::Doc::INTRO
@@ -195,9 +195,19 @@
   # <tt>rio(?`,cmd)</tt> (mnemonic: '`' (backtick) runs an external program in ruby)
   #
   # <tt>rio(:cmdio,cmd)</tt>
   #
   # This is Rio's interface to IO#popen
+  #
+  # ===== Creating a Rio that acts like /dev/null
+  #
+  # <tt>rio(nil)</tt>
+  #
+  # <tt>rio(:null)</tt>
+  #
+  # This rio behaves like the Unix file /dev/null, but does depend on it -
+  # and thus will work on non-Unix systems. Reading behaves as if reading from
+  # an empty file, and writing to it discards anything written.
   #
   # ===== Creating a Rio Pipe
   #
   # A Rio Pipe is a sequence of Rios that are run with the output of each being
   # copied to the input of the next.