In the MS Windows environment, you must load the DOS Requester, BREQUEST.EXE, before starting MS Windows. MS Windows-based Btrieve applications access the requester by means of a DLL, WBTRCALL.DLL, which uses the DOS Protected Mode Interface (DPMI) that MS Windows provides.
The MS Windows Requester (that is, WBTRCALL.DLL) is the Btrieve interface DLL for MS Windows 3.x. The DLL provides the same API as client-based Btrieve and requires no modification to the application.
You can access local as well as remote files by running both client-based (local) Btrieve and the MS Windows Requester at your workstation. If you want to run both client-based Btrieve and the requester, you must also run the MS Windows Conversion utility (WNDBCNVT.EXE) to convert the client-based WBTRCALL.DLL to WBTRLOCL.DLL.
NOTE: Client-based Btrieve is available only as part of the Btrieve Developer's Kit, which is available through Btrieve Technologies, Inc. at 1-800-BTRIEVE and must be purchased separately.
The following list describes the available configuration options for the MS Windows Requester. These options should be specified in the NOVDB.INI file under [brequestDPMI].
NOTE: NOVDB.INI is the Novell® initialization file for the MS Windows Requester. It is included on the distribution diskette
| NOTE: Tasks=# | NOTE: Specifies how many concurrent tasks may use the MS Windows Requester. The range is 1 through 255. The default value is 10. |
| NOTE: Local=Yes/No | NOTE: Instructs the MS Windows Requester to use client-based Btrieve for accessing files locally. The default value is No. |
| NOTE: Chkparms=Yes/No | NOTE: Instructs the MS Windows Requester to validate all Btrieve call parameters passed to it. (Use this option only for debugging during development.) The default value is No. |
| NOTE: Free Memory=Yes/No |
NOTE: Allocates and frees real-mode memory on each request.
The MS Windows Requester uses a buffer of real-mode memory to communicate with the DOS Requester. Since real-mode memory is a scarce resource in MS Windows, the application should not retain it long- term. The default value is No. |
IMPORTANT: Specifying Yes to the Free Memory option degrades performance.
The DOS Requester must be loaded before the MS Windows Requester can load. If you want to run MS Windows-based Btrieve applications, the DOS Requester must be loaded in the DOS environment before you start MS Windows.
To load the DOS Requester, use the WINSTART.BAT file, or enter the following at the DOS prompt before loading MS Windows:
brequest
An application may load the MS Windows Requester in one of the following ways:
When an application loads a DLL implicitly, the operating system automatically loads the DLL when the application is started.
The operating system does not load the DLL until notified to do so.
IMPORTANT: If you want to run a DOS-based Btrieve application in the DOS box and a MS Windows-based Btrieve application in MS Windows at the same time, you must have the DOS Requester loaded in each DOS session. However, if you have already loaded the DOS Requester before loading MS Windows, you cannot load the DOS Requester in any subsequent DOS session. Consequently, you cannot run the DOS-based Btrieve application in the DOS box.
IMPORTANT: For MS Windows applications using the DOS Requester, load BREQUEST outside Windows. In each MS Windows DOS session that will be running a Btrieve application, load BREQUEST with the /L option. Doing so loads another instance of BREQUEST that is available only to the DOS session. This operation provides the DOS session with its own copy of BREQUEST and prevents the DOS session from using the instance of BREQUEST that you loaded before starting Windows.
At a MS Windows workstation, the operating system removes the dynamic link routines from memory when the application terminates, or when the application explicitly unloads the DLLs using the operating system API functions.
NOTE: If Btrieve files are left open in an application because the application did not issue a Close (1) operation, simply logging out of one or more servers from a workstation does not close the files or terminate the Btrieve SPX connection to the server. The files remain open until you reboot the workstation, unload the DOS Requester using BREQUTIL -STOP, or execute a reset operation using BREQUTIL -RESET. (Remember, however, that a reset operation does not unload the DOS Requester.)