TEGetScrapLen
returns size of TextEdit scrap, in bytes
For System 4.1 and later, you may use InfoScrap and other Returns: a 32-bit long int; the size of the contents of the TextEdit scrap.
Notes: The global variable TEScrpLength (at 0x0AB0) contains this
same information.
Notice that the return value is a 32-bit long int (one might be led to
expect a 16-bit value).