How do I set up isCOBOL to access Vision files?

Question:
What do I need to do to access Vision files from isCOBOL?

Answer:

isCOBOL 2023R1 and later
isCOBOL 2023R1 added an interface to the Vision file system called VisionJ. You can create, write, read, and lock Vision files using this interface by setting file index:

   iscobol.file.index=VisionJ

Compression is supported with this file handler, but encrypted files and transaction logging are not.
If you need to access Vision files with encryption or use transaction logging, you should use the vfc (Vision File Connector) described below.

isCOBOL 2022R2 and earlier
In order to access Vision you can build a Vision File Connector (vfc) and set iscobol.file.index to "vfc".

Building the vfc
This vfc, runcbl.dll (or libruncbl.so on Unix/Linux), is a specially relinked version of Acucorp's wrun32.dll (or libruncbl.a on Unix/Linux). You will need Microsoft Visual Studio standard edition in Windows or a C compiler and linker in Unix/Linux to build your vfc yourself.
If you want Veryant to create this file for you, you can send us all of the files in your Acucorp lib directory and tell us exactly which version of ACUCOBOL you have installed and the name and version of the operating system.
Setting up your environment
The vfc depends on other DLLs that are in the AcuGT/bin directory. So make sure that AcuGT/bin is in PATH or that those DLLs are in a directory which is in PATH.
You need a valid Acucorp runtime license in the PATH as well.
Assigning the vfc to your files
Once you have the vfc built and your environment set up, add the following line to your isCOBOL properties file to set all file access to the vfc:
```
   iscobol.file.index=vfc
```
or this line to set up a single file if only one or some of your files are in the Vision format:
```
iscobol.file.index.FileName=vfc
```
FileName is the physical name of your file, but it must be written in lowercase in the properties file.
For example, if you have:
```
   select mylogicalfile assign to "MyPhysicalFile"
```
then you would set: iscobol.file.index.myphysicalfile=vision Note that: if you have iscobol.file_suffix=DAT you must specify the file extension in all lowercase in the iscobol.file.index.FileName variable. For example:
```
   iscobol.file_suffix=DAT iscobol.file.index.myphysicalfile.dat=vision
```