Fix call-seq in RDoc.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@10790 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ext/io/wait/wait.c

@@ -42,8 +42,7 @@ EXTERN struct timeval rb_time_interval _((VALUE time));
 
 /*
  * call-seq:
- *
- *   io.ready? -> boolean
+ *   io.ready? -> true, false or nil
  *
  * Returns non-nil if input available without blocking, or nil.
  */
@@ -81,9 +80,8 @@ wait_readable(VALUE p)
 
 /*
  * call-seq:
- *
- *   io.wait          -> io, true, false or nil
- *   io.wait(timeout) -> io, true, false or nil
+ *   io.wait          -> IO, true, false or nil
+ *   io.wait(timeout) -> IO, true, false or nil
  *
  * Waits until input is available or times out and returns self or nil when
  * EOF is reached.