Add wait_for_internet.py.

wait_for_internet.py

@@ -0,0 +1,38 @@
+'''
+wait_for_internet
+=================
+
+This program will block until internet access is available. It can be useful to
+run this program before running another program that expects an internet
+connection.
+
+> wait_for_internet timeout
+
+timeout:
+    An integer number of seconds, after which to give up and return 1.
+'''
+import argparse
+import sys
+
+from voussoirkit import betterhelp
+from voussoirkit import networktools
+from voussoirkit import vlogging
+
+def wait_for_internet_argparse(args):
+    try:
+        networktools.wait_for_internet(timeout=args.timeout)
+        return 0
+    except networktools.NoInternet:
+        return 1
+
+@vlogging.main_decorator
+def main(argv):
+    parser = argparse.ArgumentParser(description=__doc__)
+
+    parser.add_argument('timeout', type=int)
+    parser.set_defaults(func=wait_for_internet_argparse)
+
+    return betterhelp.single_main(argv, parser, __doc__)
+
+if __name__ == '__main__':
+    raise SystemExit(main(sys.argv[1:]))