>I would like to have a function to validate filenames.


Try: http://msdn.microsoft.com/en-us/library/bb776472%28v=VS.85%29.aspx

It uses a windows shell function to validate the pathname for the destination (such as enforcing 8.3 file format on drives that only support 8.3).

It only supports wide character format, so you'll have to convert the text first.

Use STRCONV() 1 and 5 to encode, then 6 and 2 to decode (see http://msdn.microsoft.com/en-us/library/k0yb2181%28v=vs.80%29.aspx).

Use DECLARE DLL function to declare the function. And use @ at signs on your strings.

HTH!