test repeated open/close of 1000 files

testsuite/tests/ghc-regress/lib/IO/all.T

@@ -69,6 +69,8 @@ clean(['openFile006.out'])
 test('openFile007',  compose(expect_fail_if_compiler_type('hugs'),
 			expect_fail_if_windows), compile_and_run, [''])
 clean(['openFile007.out'])
+test('openFile008', normal, compile_and_run, [''])
+
 test('putStr001',    normal, compile_and_run, [''])
 test('readFile001',  compose(expect_fail_if_compiler_type('hugs'),
 			expect_fail_if_windows), compile_and_run, [''])

testsuite/tests/ghc-regress/lib/IO/openFile008.hs

+import System.IO
+import System.Cmd
+import System.FilePath
+import Text.Printf
+import System.Directory
+import Control.Monad
+
+testdir = "openFile008_testdir"
+
+-- Test repeated opening/closing of 1000 files.  This is useful for guaging
+-- the performance of open/close and file locking.
+main = do
+  system ("rm -rf " ++ testdir)
+  createDirectory testdir
+  let filenames = [testdir </> printf "file%03d" (n::Int) | n <- [1..1000]]
+
+  forM_ [1..50] $ \_ -> do
+    hs <- mapM (\f -> openFile f WriteMode) filenames
+    mapM_ hClose hs
+
+  mapM_ removeFile filenames
+  removeDirectory testdir