1 files changed, 6 insertions, 0 deletions
diff --git a/ext/pty/lib/expect.rb b/ext/pty/lib/expect.rb
index 08191b05b9..50d2fbd363 100644
--- a/ext/pty/lib/expect.rb
+++ b/ext/pty/lib/expect.rb
@@ -1,6 +1,12 @@
 $expect_verbose = false
 
 class IO
+  # Reads ios until pattern matches or the timeout is over. It returns
+  # an array with the read buffer, followed by the matches. If a block is given,
+  # the result is yielded to the block and returns nil. The optional timeout parameter defines,
+  # in seconds, the total time to wait for pattern. If it is over of eof is found, it 
+  # returns/yields nil. However, the buffer in a timeout session is kept for the next expect call.
+  # The default timeout is 9999999 seconds.
   def expect(pat,timeout=9999999)
     buf = ''
     case pat