install.py: add note about parse_known_args

diff --git a/bin/install.py b/bin/install.py
index 3fdd5be3b16c15a6257d7d5466e1c7bd25869a38..2ca62f2335caaa8ecec88b5fb48d53cf6894384f 100755 (executable)
--- a/bin/install.py
+++ b/bin/install.py
@@ -142,6 +142,16 @@ def parse_args(args):
                action="store_true",
                dest="version"
        )
+
+       # Use parse_known_args for maximum compatibility with
+       # getopt handling of non-option file arguments. Note
+       # that parser.add_argument("files", nargs='+') would
+       # be subtly incompatible because it requires that all
+       # of the file arguments be grouped sequentially. Also
+       # note that we have to explicitly call add_argument
+       # for known options in order for argparse to correctly
+       # separate option arguments from file arguments in all
+       # cases (it also allows for optparse compatibility).
        parsed_args = parser.parse_known_args()
 
        opts  = parsed_args[0]