Maximum buffer size for read from magtape?

[Darrel VanBuer]

IBM 360/370 architecture machines can read and write tape blocks over 64k,
but it's tricky; you have to write your own channel program (an I/O program).
(In fact, you have to write your own to go over 32K-1, the OS treats lengths
as 16 bit signed quantity; the hardware count field is 16 bit unsigned, but
you can beat the limit by data chaining [a way to provide another address/
count pair for a continuation of an operation]

-- 
Darrel J. Van Buer, PhD
System Development Corp.
2500 Colorado Ave
Santa Monica, CA 90406
(213)820-4111 x5449
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                                                            !sdcrdcf!darrelj
VANBUER at USC-ECL.ARPA