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Important: This document is part of the Legacy section of the ADC Reference Library. This information should not be used for new development.

Current information on this Reference Library topic can be found here:

What is SetMovieDefaultDataRef?

Q I can't find documentation for the SetMovieDefaultDataRef function. What does it do, and how do I use it?
A SetMovieDefaultDataRef is defined in Movies.h as:
pascal OSErr SetMovieDefaultDataRef(Movie theMovie, Handle dataRef, OSType dataRefType);

It allows you to control where data will be written to when added to a movie. For example, if a movie was loaded from a file, the default data reference is initialized to be the file from which the movie was loaded. This example will set the default data reference to be a handle in memory: 

     OSErr ConvertGeneralMIDIToSoundTrack (void)
     {
          OSErr                              err = noErr;
          StandardFileReply                  reply;
          short                              refNum;
          long                               logicalEOF;
          Handle                             dataHandle = nil, tempHandle = nil;
          Movie                              theMovie = nil, tempMovie = nil;

          // Specify the General MIDI file to import
          StandardGetFilePreview (nil, 0, nil, &reply);
          if (reply.sfGood)
          {
               // Open the data fork and suck everything into a handle
               err = FSpOpenDF (&reply.sfFile, fsRdPerm, &refNum);
               err = GetEOF (refNum, &logicalEOF);
               dataHandle = NewHandleClear (logicalEOF);
               HLock (dataHandle);
               err = FSRead (refNum, &logicalEOF, *dataHandle);
               HUnlock (dataHandle);
               FSClose (refNum);

               // Create a new movie in memory, set its default data reference
               // to be a handle
               tempMovie = NewMovie (newMovieActive);
               tempHandle = NewHandleClear (4);
               SetMovieDefaultDataRef (tempMovie, tempHandle,
                    HandleDataHandlerSubType);
               DisposeHandle (tempHandle);

               // Paste the handled data into our movie
               err = PasteHandleIntoMovie (dataHandle, 'Midi', tempMovie, 0, nil);

               // Save the movie out to a flattened file
               StandardPutFile ("\pSave MIDI to:", "\pMIDI movie", &reply);
               if (reply.sfGood)
               {
                    theMovie = FlattenMovieData (tempMovie,
                         flattenAddMovieToDataFork, &reply.sfFile, 'TVOD',
                         smCurrentScript, createMovieFileDeleteCurFile);
               }
          }
          return err;
     }

This method works fine as long as you have enough memory, and don't want to save the movie to disk. To put data into a file, call this function in order to pass in an alias to the file as the data reference and rAliasType as the data reference type:

SetMovieDefaultDataRef (tempMovie, fileAlias, rAliasType);

[Mar 14 1997]