Expand QXL.WIN

Discussion and advice about emulating the QL on other machines.
mhanias
ROM Dongle
Posts: 46
Joined: Mon Jul 11, 2011 10:12 pm

Expand QXL.WIN

Postby mhanias » Sun May 06, 2018 9:40 pm

Is it possible to expand an existence QXL.WIN file i.e from 100MB to 200MB?


User avatar
NormanDunbar
Super Gold Card
Posts: 544
Joined: Tue Dec 14, 2010 9:04 am
Location: Leeds, West Yorkshire, UK
Contact:

Re: Expand QXL.WIN

Postby NormanDunbar » Sun May 06, 2018 10:37 pm

viewtopic.php?f=19&t=1767&p=15582&hilit=Extend+qxl.win#p15582 might help.

I think you need to create a new file and copy over the data. The size of the file determines the group size, so changing from 100 to 200 mb would change the group size from 4 to 7 and truly mess things up!

Group size 4 gives files up to 128 mb, and 7 gives up to 224 mb. The group size is the number of 512 byte sectors that each entry in the map covers, and, defines the smallest amount of space used on disc by a file.

You can read about the format of a qxl.win file at http://qdosmsq.dunbar-it.co.uk/doku.php ... sq:fs:qlwa and the group size and maximum qxl.win sizes at http://qdosmsq.dunbar-it.co.uk/doku.php ... roup_sizes.

HTH

Cheers,
Norm.


Why do they put lightning conductors on churches?
How come Tarzan never grew a beard?
If at first you don't succeed, don't take up skydiving!
If you think your job is pointless, remember, there's a man in Germany who fits indicators on BMWs.
User avatar
pjw
Gold Card
Posts: 402
Joined: Fri Jul 11, 2014 8:44 am
Location: Norway

Re: Expand QXL.WIN

Postby pjw » Mon May 07, 2018 8:30 am

NormanDunbar wrote:http://qlforum.co.uk/viewtopic.php?f=19&t=1767&p=15582&hilit=Extend+qxl.win#p15582 might help.
On Dilwyn's site you may find a "script" called QLWARZ to do exactly that. Its packaged so as to run as a single operation: stretch, copy and rename, all in one. As it stands, however, it may not be suitable for all platforms. You may need to make some adjustments to things like WIN_DRIVE or its parameters to suit your system.

I think you need to create a new file and copy over the data. The size of the file determines the group size, so changing from 100 to 200 mb would change the group size from 4 to 7 and truly mess things up!
I think "messing things up" is too strong, Norm. The trick is to choose an optimal size for the amount and sort of data you intend to store. The information in QLWARTZ provides a brief overview. Norman's wiki article gives greater detail on this.

Group size 4 gives files up to 128 mb, and 7 gives up to 224 mb. The group size is the number of 512 byte sectors that each entry in the map covers, and, defines the smallest amount of space used on disc by a file.

You can read about the format of a qxl.win file at http://qdosmsq.dunbar-it.co.uk/doku.php ... sq:fs:qlwa and the group size and maximum qxl.win sizes at http://qdosmsq.dunbar-it.co.uk/doku.php ... roup_sizes. <>


Per
For every complex problem there is an answer that is clear, simple, and wrong.
- H. L. Mencken
User avatar
NormanDunbar
Super Gold Card
Posts: 544
Joined: Tue Dec 14, 2010 9:04 am
Location: Leeds, West Yorkshire, UK
Contact:

Re: Expand QXL.WIN

Postby NormanDunbar » Mon May 07, 2018 2:24 pm

Hi Per,

When I said that it would mess things up, I meant if the file was extended to such an extent that the group size was changed but original data still remained. I thought I'd been clear, but reading back, it's obvious that I wasn't! My bad - as the youth of today might say. ;)

Cheers,
Norm.


Why do they put lightning conductors on churches?
How come Tarzan never grew a beard?
If at first you don't succeed, don't take up skydiving!
If you think your job is pointless, remember, there's a man in Germany who fits indicators on BMWs.

Return to “QL Emulation”

Who is online

Users browsing this forum: No registered users and 3 guests