Subject: Re: RL01 support in NetBSD?
To: None <port-vax@netbsd.org>
From: Megan <mbg@world.std.com>
List: port-vax
Date: 02/19/2000 15:50:28
>Well Megan. I can see you haven't played around with OS/8. :-)

Long time ago... but I was answering for RT-11...

>MACREL there has just this problem. Actually, the solution is simple. You
>do several passes, doing one thing each pass. Pass 1: Generate symbol
>table. Pass 2: Output object file. Pass 3: Generate list file. Pass 4:
>Cross reference.

Yes, I know about doing multiple passes...

>But I can see that RT-11 is an improvement over OS/8 here. (And John
>Wilson also pointed this out).

Yes... and I responded before I saw his response... ah well...

>OS/8 don't support extending files. You might fix it by fiddling with the
>directory block yourself, if you have an empty slot after your file.

Same thing with RT-11... or you could have a specialized routine which
.ENTERs a new file by the same name, with a larger size, copies all
the blocks over, then closes the old file and continues writing the
new one until done (or until you hit EOF again).

>Sounds very much like OS/8 here. But if you have a bootable system, the
>first directory block is at 60 instead of 7. (Might remember the block
>numbers wrong, however...)

That may be for OS/8, but 6/7 is most definitely the first segment for
RT-11.  Boot block is zero, with secondary boot in 2-5.  Home block is
block 1, with info about the rest of the disk.  Directory in 6/7 at
a minimum... data blocks starting no later than 68.

					Megan Gentry
					Former RT-11 Developer

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