RISC World

VirtualAcorn Tech Support

More from Aaron's tech support notebook

HostFS for Windows

As every VirtualAcorn users knows the main filing system for VirtualAcorn products is HostFS. Over the last few months we have been re-writing the Windows versions of HostFS to deal with a couple of long standing niggles with regard to RISC OS file datestamps. The problems were too fold. Firstly copying a file from another RISC OS filing system to HostFS would result in the datestamp of a file being set to the time the file was copied. Secondly if a user opened an archive (zip, ArcFS etc) under VirtualAcorn but did not alter the contents the datestamp of the archive would be reset to the time and date the file was opened.

The problem isn't quite as simple as it looks. RISC OS has one datestamp, but Windows, which holds the underlying HostFS drive data, as three. These are created (when the file was made), Modified (when the file was last altered) and Accessed (when it was last loaded). The problem is that none of the Windows datestamps exactly match the RISC OS one. As an example, if HostFS was to use the Windows "created" date stamp then files might retains their datestamp of copied from HostFS to HostFS. But if copied from ADFS to HostFS the file would be "new" and would be give a current datestamp. Any further attempt to "reset" the datestamp under RISC OS would fail, because it would be the Windows "Modified" entry that would be updated. Using either of the other two datestamps has similar problems.

In the end we decided the only proper solution would be to reproduce what a native RISC OS filing system does. In order to do this we re-wrote HostFS to cache the datestamps of files when a file was opened and to write the datestamp data back when the file was closed. This sounds quite trivial, but in reality it's taken several months to get right. This is mainly because RISC OS can have a large number of files open at any one time. We have made several new releases of HostFS since last autumn and come the middle of December we were convinced that we had it cracked...

Until the second week of January all seemed to be well, then we started getting some really weird problem reports. A bit of detective work with the help of a couple of users finally tracked the problem down. When printing on VirtualAcorn the print job is sent to file (HostFS::printername). This file is then sent into the Windows print queue. What was happening was that the datestamp preservation code was trying to set the datestamp of the printjob in the Windows queue. Unsuprisingly this would fail. Then the code would get itself confused and fail to set the datestamp and filetype for any file that was subsequently closed. The result was that any file saved from this point on would be set as a Textfile, and nothing could be done to change the filetype.

Whilst the number of machines effected was small this was serious. So we busted the weekend and midnight oil and have made some important changes to HostFS. Whilst the fault only showed up on some machines it could (in theory) happen to any VirtualRPC running a version of HostFS from Sept 2008 to 15th January 2009. As a result we have released a new HostFS Update for all versions of VirtualRPC and removed all the previous Sept to December updates.

We strongly advise anyone using VirtualRPC to apply these updates (which can be downloaded from the VirtualAcorn website) or found in the Software directory of this CD, as a matter of urgency. If you haven't already had the problem, then you probably won't, but you might. Isn't software development fun...

Windows 7

You may be aware that Microsoft is pushing the release schedule of Windows 7 forward. This is no doubt a response to the very poor takeup of Windows Vista, especially among businesses. Whilst Vista sales are in themselves acceptable the vast majority of copies in use have come bundled with computers. So bad has the general reception of Vista been that some manufacturers also ship a Windows XP "Downgrade CD". Perhaps "Upgrade CD" would be a better name as XP is faster, more compatible and has fewer problems.

We always test VirtualRPC on beta versions of Windows prior to Microsoft's release and this time it's no different. Shown below is a screenshot of VirtualRPC running RISC OS 6 on Windows 7.

VirtualRPC running RISC OS 6.14 on Windows 7

There are a few non fatal niggles that with some of the Windows 7 drivers, but no doubt these will get fixed before this new version of Windows gets a full release. We will continue testing Windows 7 as it evolves.

Reg card wonderment

All the products we supply come with a registration card that needs to be returned to us. Looking through the records over 90% of people return these cards. This is a very good high figure and I'm very pleased with the return rate. Sometimes people forget and if they ring up for support, or to obtain a new unlock code then we will remind them to return the card. It's important for us to know who has which product and the serial number of the product itself. If we do ever need to contact the person having these details is rather important.

The registration cards themselves need to be filled in with an address, which we never share with any third party, and some serial numbers from the CD and the RISC OS licence sticker. For overseas users who have un-reliable postal systems we sometimes suggest that they return the details via an e-mail. This brings me neatly to the point of this section. We have a customer who has a number of VirtualRPCs in an Arabic country. They have never returned the registration cards and since the products were purchased via a dealer in New Zealand (don't ask) we still don't know who they really are. Recently they needed to replace a machine and hence needed to get a new unlock code. I issued then code and then asked them to return the filled in registration cards. This is what arrived via e-mail:

The returned registration card.

Still at least it will be handy if I ever forget our address.


Finally, as they say at the end of the news, I would like to point out that currently we have a sale on at the VirtualAcorn website. We have slashed the prices of all the products, with a base level VirtualRPC-SE now starting at £51.50 including p&lp. The top level VirtualRPC-AdjustSA for either Windows or MacOSX is reduced to only £81.50 including P&p. So if you are considering purchasing a copy now could be a good time. That is the end of blatant is the end of the news.