Using the dialog layer
The VA Smalltalk proc dialog parts provide a way for your client applications to communicate with another program using a simple dialog.
Proc dialog is short for procedure dialog. A proc dialog follows a predefined sequence of steps:
1. Connect to the remote machine
2. Send data to the remote machine
3. Receive data from the remote machine
4. Disconnect from the remote machine
If your client and server applications are designed to follow this sequence, you can use a VA Smalltalk proc dialog part to perform your communications functions.
To a VA Smalltalk application, a proc dialog part behaves very much like the C and COBOL External Function parts, which are used to access functions residing in local DLLs. As with a local DLL function, a proc dialog communicates with the server program logic through a record, a formatted chunk of data that is both passed to and received from the server. When a VA Smalltalk application runs the proc dialog, it passes the proc dialog a single record, which can contain both input and output fields. When the function completes, the output fields are filled in with the function's result values. Refer to the Visual Programming User Guide for more information on interfacing to DLLs.
Unlike the DLL external function parts, the proc dialog parts do not support the passing of multiple records. All of the necessary input and output fields must be contained in a single record.
Last modified date: 07/25/2020