Changed dbfile argument to be optional, default to ~/.dwtt.db

dwtt

@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 
+import os
 import sys
 import getopt
 from datetime import datetime
@@ -11,7 +12,7 @@ from DataStore import DataStore
 PROGRAM_NAME = 'dwtt'
 
 def usage():
-    print '''Usage: dwtt [options] <dbfile>
+    print '''Usage: dwtt [options] [dbfile]
   Options:
     --help                  Show this help
 '''
@@ -33,10 +34,9 @@ def main(argv):
             usage()
             sys.exit(3)
 
-    if len(args) < 1:
-        usage()
-        sys.exit(2)
-    timedbfile = args[0]
+    timedbfile = os.path.expanduser('~') + os.path.sep + '.dwtt.db'
+    if len(args) >= 1:
+        timedbfile = args[0]
 
     ds = DataStore(timedbfile)