In article <102.2B7ECA62@purplet.demon.co.uk> jaggy@purplet.demon.co.uk (Mike Jagdis) writes:
quoted text
>* In message <892@esquire.dpw.com>, Colin Jenkins said:
>
>CJ> I run Xenix, Linux, MSDOS, and Windows 3.1.  Since I have to
>CJ> allocate separate swap areas for everything (except DOS), I am
>CJ> "wasting" lots of space.  Has anyone found ways to share swap areas?
>
>The key is probably to use a partition for swap space. When you boot Linux 
>you need to have it do an mkswap on the partition and then swapon on it (see 
>bootsys3.taz). When you boot Xenix you want to have it swap in the partition 
>rather than looking for a divvy'd area within it. I can't think wether or 
>not this is possible off hand. It ought to be. Try looking at the boot man 
>pages. With Windoze you would need to put a format command in autoexec.bat 

I have thought of this, but was hoping to be able to allocate the swap
dynamically.  The real problem is with Xenix.  Although not documented, I
suspect that I can get it to look into a spare partition by linking
/dev/swap to a spare fdisk partition device in dev.  I had already given 
some thought to formatting such a partition and creating the swap file 
when windows starts.  Since I don't know for certain that I can change the
Xenix swap device, I might be down for a couple of days 
testing/failing/restoring Xenix.

I have a couple of problems with the paritition idea: 

        1) I don't have a spare partition!  Fortunately I do have a tape
           drive, but I don't relish the thought of spending a day reinstalling
           xenix so that I can break the divvy partition out into a separate
           fdisk partition.

        2) Allocating a partition for swap means that I will be stuck with
           a small partition (I probably wouldn't need more that 16 meg) and
           changing swap sizes would be just as difficult as creating the
           intial swap area.

Right now I am working on getting Xenix divvy partitions supported under
the Linux Xenix fs.  If I can do that, then I also get the added benefit of
true access to my Xenix files (which I don't have because I don't have a
dedicated non-divvy Xenix partition).  I looks like it should be easy, so I
am going start there.  If there is interest and I am successful I'll make
the patches available somehow.

Thanks for the suggestions.

                                                Colin