Playmod flag in custom importer

Hi All,

I noticed the following note in SDK_Custom_Import.cpp for SDKGetPrefs8 function.

"Note: the timelineData handle is new, and allows ONLY custom importers

    access to the timeline (dont' use with a synth or standard importer).

    The timeline handle provide the importer with the ability (and the know-how)

    to parse the timeline, searching for the clip with the playmod flag

    indicating it is the currently selected clip. This flag will be set

    when the user double-clicks the custom imported clip on the timeline and

    Premiere calls the importer to modify the file."

Can any one tell me where "playmod flag" is defined?

Thanks & Regards,

Chandan