ndi.file.temp_fid

  TEMP_FID - open a new temporary file for writing

  [FID,FNAME] = TEMP_FID()

  Open a new temporary file for writing. The full name of 
  the file is returned in FNAME and the file identiifer is
  returned in FID.

  The file is opened for writing and little-endian byte order,
  the NDI default.

  An error is produced if the operation fails.