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X-Hacker.org- FiveWin 1.9.2 - January 97 - <b>3.1 reusing all your msdos designs</b>
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3.1 Reusing all your MsDos designs
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FiveWin imposes no restriction at all to your current DataBase designs
and techniques acquired in MsDos. You may feel free to continue
working as you normally do with DataBases.
There are just some points you should keep in mind for a better
understanding of Windows processes:
1.- By default any Windows task is given a maximum of 20 files
opened at the same time. In order to have the same conditions as we
have in MsDos you have to use the SetHandleCount() function that
FiveWin supplies:
SetHandleCount( <nMaxFiles> ) --> <nMaxFilesAutorized>
If your application is going to manage 40 files at the same time, you
will have to do at the beginning of your application:
SetHandleCount( 40 )
Remember that DBFs that use memos also open an associated file DBT, and
also remember that normally when Windows is printing it opens some
temporary files (also FiveWin opens some more when doing PREVIEWs of
printing works). If you get an error it may be that there are not
enough files available. Increase its number with SetHandleCount().
There is a maximum of 255 files available per application.
Also it is not a good idea to give 255 files to all your applications
for you will consume a lot of memory resources!
2.- If you are working with NonModal designs, the same DataBase may
get opened several times at the same time! By the same user! Clipper
allows this but, in fact, your application is acting like an application
for a NetWork. You have to provide Multi-User control to your application!
For this, if you are using Windows 3.1 loading SHARE.EXE before loading
Windows, this is a MUST! If you are using Windows 3.11 or Windows 95
(pre-releases versions) this is no needed as these new versions
automatically load SHARE.EXE when starting.
Converting an application for working in a NetWork is quite easy.
Review this documentation for our recommendations and guidance for
NetWork programming. Don't worry if you have never code a multi-user
application. It is really easy!
3.- FiveWin offers you a powerful DataBase Class that in fact saves
you a lot of tedious work. Just give a little of your time to understand
the FiveWin DataBase Class and you will save a lot of your precious
time!
DataBase objects saves you from coding a _lot_ of source code lines!
Go for DataBase objects right now!
4.- If you are working with older versions of CA-Clipper (older than
5.2 d) you may have serious troubles working with some CA-Clipper
RDDs. Some of them cause big problems in MsDos but in Windows they
may crash your system. DbfCdx is not working properly even in version
5.2 d. There is a late patch for 5.2 d but we have not tested it yet,
since we work most of the time, with Comix and SixDriver.
We do recommend working with compound indexes CDX as they save a lot
of work. Get Comix or SixDriver and use them! They are excellent!
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