C3D.is_c3d
nStatus = C3D.is_c3d( FileName AS STRING ) AS INTEGER
Returns C3D_SUCCESS if a C3D file
Example:
PRINT "Testing if File is C3D: "
PRINT C3D.GET_ERROR_MESSAGE( C3D.IS_C3D( "e:\maxpro\demo files\hand.c3d" ) ),