[comp.sys.tandy] Model 100 programming help

alistair@ubc-bdcvax.UUCP (Alistair Blachford) (07/25/90)

Sure could use some hints for two problems:

1.	I'd like to periodically update just one record of a database
(.DO file) with fixed length records.  (A write of the whole file
takes too long.)  Any tricks?  I'd like to stick to BASIC if possible. 
I know that VARPTR can be used to return the address of the file
control block for a file descriptor, but I do not know the structure
of a file control block, or how to find the address (from BASIC) of
the first character of the .DO file.  Since the records are of fixed
length, I figured I could work from there, to do the selective record
updating ...

2.	What is the way to fix things so that control-c will not break
the execution of a BASIC program.  I only want shift-break to be able
to do this.  I note that my LAPDOS.BA program has this feature (but
peering at it does not help!).

I'd be interested to know of where I can find any books/documentation
on this kind of topic.

	Thanks for any help!

alistair@uu.bdc.ubc.ca
Alistair Blachford
Biosciences Data Centre, UBC
Vancouver, BC  Canada
(604)228-2645
-- 
Alistair Blachford			(604)228-2645
Biosciences Data Centre			Internet: alistair@bdc.ubc.ca
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