Inside Macintosh: QuickTime /

Chapter 2 - Movie Toolbox / Movie Toolbox Reference

Functions That Modify Movie Properties / Working With Movie User Data

GetNextUserDataType

The GetNextUserDataType function allows you to retrieve the next user data type in a specified user data list. You can use this function to scan all the user data types in a user data list.

pascal long GetNextUserDataType (UserData theUserData, 
                                    OSType udType);

theUserData

Specifies the user data list for this operation. You obtain this list reference by calling the GetMovieUserData, GetTrackUserData, or GetMediaUserData function (described on page 2-215, page 2-216, and page 2-217, respectively).

udType

Specifies a user data type. Set this parameter to 0 to retrieve the first user data type in the user data list. On subsequent requests, use the previous value returned by this function.

DESCRIPTION

The GetNextUserDataType function returns an operating-system data type containing the next user data type value in the specified user data list. When you reach the end of the user data list, this function sets the returned value to 0. You can use this value to stop your scanning loop.

ERROR CODES

None