Try harder to prevent file lost.


git-svn-id: http://opensvn.csie.org/pttbbs/trunk@5978 63ad8ddf-47c3-0310-b6dd-a9e9d9715204
Add missing def.


git-svn-id: http://opensvn.csie.org/pttbbs/trunk@5979 63ad8ddf-47c3-0310-b6dd-a9e9d9715204