You must load the Btrieve DOS Requester, BREQUEST.EXE, at a workstation running DOS before that workstation can access network Btrieve files using the Btrieve NLM. The DOS Requester loads into a DOS workstation's memory as a Terminate and Stay Resident (TSR) program.
You can access local as well as remote files by running both client-based (local) Btrieve and the requester at your workstation.
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.
There are five configuration options for the NetWare Btrieve DOS Requester:
NOTE: Previous versions of the DOS Requester also supported the /S and /R options. The DOS Requester 6.x accepts the /S and /R options for backwards compatibility but otherwise ignores them.
Range: None
Default: /C:1
Memory Required: Not applicable
This option allows you to enable or disable NetWare Runtime server support.
/C:0 | /C:1 | /C:1,username,password
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/C:0 |
Disables NetWare Runtime server support. | ||
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/C:1 |
Enables NetWare Runtime server support. Btrieve looks at the username for the drive (current server) on which you are presently running. If the username is SUPERVISOR, Btrieve searches for another username in the table of usernames for the servers onto which you are logged. If the username is not SUPERVISOR, Btrieve searches for that username on the NetWare Runtime server. If it is not a valid username, Btrieve returns an error at the time of the Open or Create request./1,usernamepassword | ||
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Enables NetWare Runtime server support. Btrieve verifies the specified username and password for the NetWare Runtime server, returning an error if the specified username is not found or the password is invalid. | ||
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username |
Preferred login name on the NetWare Runtime server. If you specify SUPERVISOR for the username, Btrieve returns an error and the DOS Requester will not load. | |
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password |
Login password for the specified user. | |
For information on using Btrieve with NetWare Runtime, see "Using NetWare Btrieve with NetWare Runtime" in Chapter 3, "Installing and Configuring NetWare Btrieve."
Range: 532 through 57,000 bytes
Default: 4,096 bytes
Memory Required: 538 bytes + data message length
This option specifies the length of the largest record (or the largest portion or chunk of a record) you want to access through Btrieve. If you omit this option, the requester uses the default value, 8,192.
The DOS Requester uses this value to calculate the length of the data message buffer reserved for passing records between NetWare Btrieve and your applications. The requester maintains one copy of the data message buffer.
The value you enter here should not exceed the largest record size you configure for NetWare Btrieve through the Setup utility, as that is the maximum message that BSPXCOM can receive. (For more information, refer to the section "Largest Record Size" in Chapter 3.)
Specify the data message length in bytes. For example, if the largest record your application uses is 3,000 bytes, specify the /D option as follows:
/d:3000
NOTE: Specifying a higher value than you need for the /D option does not improve performance and may waste memory.
Range: Not applicable
Default: Not applicable
Memory Required: Not applicable
This option allows you to load another instance of BREQUEST even if one is already loaded. This option is useful if you want to run MS Windows-based Btrieve applications using the DOS Requester while running DOS VM applications that also use the DOS Requester.
To run MS Windows applications that use the DOS Requester, you must load BREQUEST before starting MS Windows. In order to run DOS applications in MS Windows, you must load BREQUEST in each DOS session. However, if you load BREQUEST outside MS Windows, you cannot load it again in a DOS session.
For MS Windows applications using the DOS Requester, load BREQUEST outside MS 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 that 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 MS Windows.
Range: None
Default: No compression
Memory Required: Approximately 32 KB on the workstation and 32 KB per client on the server
In many cases (such as when implementing extended reads or when using VATs), this option can help reduce network traffic by reducing the number of packets required to complete a request to NetWare Btrieve.
Using this option may, however, adversely affect memory and performance. Compressing and decompressing data takes extra CPU time on both the server and client sides. Because of overhead, you should not use this option with fast networks or with slow workstations for clients.
The /? option lists the other options that are available (/C, /D, and /O) and mentions that although the /S and /R options are accepted for backwards compatibility, Btrieve 6.x ignores them.
Load the DOS Requester at the workstation by entering the following command:
[path] BREQUEST [option]
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path |
The pathname to the directory where the DOS Requester is stored. You can omit the pathname if the DOS Requester is stored on the default drive or if it is located in a directory in your search path. |
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option |
Any of the configuration options (/C, /D, /L, /O, or /?). |
For example, if the requester is on the default drive and you want to specify a 2,048-byte data message length, enter the following:
brequest /d:2048.
NOTE: The forward slash (/) before the configuration option is the only valid character you can use. If you specify a dash (-) or a backslash (\), the DOS Requester may load improperly.
The DOS Requester utility, BREQUITIL.EXE, has three commands that enable you to perform the following tasks:
To unload the DOS Requester, enter the following at the workstation where the requester is loaded:
brequtil -stop
NOTE: If files have been left open, as happens, for example, when an application does not issue a Close (1) operation for each open file, simply logging out of one or more servers from a workstation does not close Btrieve files or terminate the Btrieve SPX connection to the server. While BREQUTIL -STOP does perform these tasks, it does not necessarily release all the workstation resources.
To release all the resources used by Btrieve at a workstation, you must execute the BREQUITIL -RESET command, which performs a Btrieve Reset (28) operation:
brequtil -reset <Connection ID>
The RESET command aborts any pending transactions, releases all locks, and closes all open files for the workstation. It does not, however, unload the DOS Requester, so you should first enter the STOP command and then the RESET command.
To determine the version of your DOS Requester, enter the following command:
brequtil -ver