1 files changed, 28 insertions, 0 deletions
diff --git a/testsuite/tests/concurrent/should_run/conc003.hs b/testsuite/tests/concurrent/should_run/conc003.hs
new file mode 100644
index 0000000000..c7b1f9a56c
--- /dev/null
+++ b/testsuite/tests/concurrent/should_run/conc003.hs
@@ -0,0 +1,28 @@
+module Main where
+
+import Control.Concurrent
+
+-- simple handshaking using two MVars, 
+-- must context switch twice for each character.
+
+main = do
+  ready <- newEmptyMVar
+  datum <- newEmptyMVar
+  let 
+    reader = do
+	putMVar ready ()
+	char <- takeMVar datum
+  	if (char == '\n') 
+		then return () 
+		else do	putChar char; reader
+
+    writer "" = do
+	takeMVar ready
+	putMVar datum '\n'
+    writer (c:cs) = do
+	takeMVar ready
+	putMVar datum c
+	writer cs
+
+  forkIO reader
+  writer "Hello World"