[Info-vax] fixing a saveset's attributes: attachment, not ftp

[Stephen Hoffman]

On 2015-06-23 19:24:52 +0000, David Froble said:

> I haven't seen the sources, so this is some guesses.
> 
> JF Mezei wrote:
>> 
>> You can do a $READ of 4096 bytes even if the LRL is 512 bytes, right ?
> 
> I have no idea how to do that, without an appropriately sized buffer.

If you're inclined to do this the easy way, simply map the first eight 
512-byte blocks into virtual memory (if you really want to see 4096 
bytes of stuff), and go rummage through virtual memory.

The C mmap() call is simple, or you can use $crmpsc or such if you 
wanted to work a little more.

I've previously posted some C code that uses mmap[1] and rummages 
through data structures, and some other example C code that 
demonstrates some of the "newer" process section system services[2].

———
[1] http://labs.hoffmanlabs.com/node/1906
[2] http://labs.hoffmanlabs.com/node/1771

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