diff --git a/HScope.hs b/HScope.hs
--- a/HScope.hs
+++ b/HScope.hs
@@ -18,6 +18,7 @@
 import Control.Applicative ((<$>), (<*>))
 import System.IO (hFlush, stdout)
 import Data.Generics.Uniplate.Data (transformBiM)
+import System.Directory (doesFileExist)
 import Data.Data
 
 data Flag = Build Bool | File FilePath | Line | Query String | CPPInclude String deriving (Show)
@@ -183,12 +184,17 @@
 main = do
     (flags, rest, _) <- fmap (getOpt Permute options) getArgs
     let cfg = parseFlags flags
-    when (cBuild cfg) $ cdbMake (cFile cfg) $ mapM_ (buildOne cfg) rest
+    when (cBuild cfg) $ do
+        if null rest then putStrLn $ "Please provide files to build the hscope database"
+                     else cdbMake (cFile cfg) $ mapM_ (buildOne cfg) rest
     if null flags then usage else go cfg
     where usage = do
             pn <- getProgName
             putStrLn $ usageInfo ("Usage: " ++ pn ++ " [OPTION...] files...") options
           go cfg = do
-            cdb <- cdbInit $ cFile cfg
-            maybe (return ()) (handleQuery cdb) $ cQuery cfg
-            when (cLine cfg) $ runLines cdb
+            b <- doesFileExist $ cFile cfg
+            if b then do
+                    cdb <- cdbInit $ cFile cfg
+                    maybe (return ()) (handleQuery cdb) $ cQuery cfg
+                    when (cLine cfg) $ runLines cdb
+                 else putStrLn $ cFile cfg ++ " does not exist"
diff --git a/hscope.cabal b/hscope.cabal
--- a/hscope.cabal
+++ b/hscope.cabal
@@ -1,5 +1,5 @@
 Name:           hscope
-Version:        0.1
+Version:        0.1.1
 License:        BSD3
 License-File:   COPYING
 Category:       source-tools
@@ -37,7 +37,7 @@
     Main-Is: HScope.hs
     GHC-Options: -Wall
     Build-Depends: base (< 5), hs-cdb, haskell-src-exts, mtl, uniplate, cereal
-                             , vector, bytestring, process
+                             , vector, bytestring, process, directory
     Default-Language: Haskell2010
 
 test-suite Build
diff --git a/t/Build.hs b/t/Build.hs
--- a/t/Build.hs
+++ b/t/Build.hs
@@ -23,7 +23,7 @@
 
 main :: IO ()
 main = withTemporaryDirectory "/tmp/hscope_test_XXXXXX" $ \td -> testSimpleMain $ do
-    plan 42
+    plan 43
     hpath <- liftIO $ canonicalizePath "./dist/build/hscope/hscope"
     tfile <- liftIO $ canonicalizePath "./t/files/Simple.hs"
     ec1 <- liftIO $ system $ "cd " ++ td ++ " && " ++ hpath ++ " -b " ++ tfile
@@ -125,5 +125,8 @@
 
     res16 <- liftIO $ readProcess hpath [] ""
     is res16 res15
+
+    res17 <- liftIO $ readProcess hpath [ "--build" ] ""
+    like res17 $ "Please provide files to build the hscope database"
 
     return ()