Configuration Variables

Data compression can now be performed at the internal socket layer. The type of compression is set with a new configuration option, AGS_SOCKET_COMPRESS. This variable must be set before any socket communication is done, and cannot be changed via SET ENVIRONMENT. The variable has three possible values:


NONE	This is the default setting. When AGS_SOCKET_COMPRESS is set to this value, no compression is performed.
ZLIB	When AGS_SOCKET_COMPRESS is set to this value, socket data is compressed using the same algorithm as the gzip compression utility.
RUNLENGTH	When AGS_SOCKET_COMPRESS is set to this value, simple compression is done, based on counting repeated bytes of data.

RUNLENGTH compression tends to be faster, while ZLIB compression tends to compress the data more, but is slower as a result.

Windows supports ZLIB compression, but not all UNIX machines do. For those machines that do not, RUNLENGTH compression is used whether this variable is set to ZLIB or RUNLENGTH. When the compression algorithm is being negotiated with a server, the method that both machines support is used.

AGS_SOCKET_ENCRYPT

Encryption support now has a uniform implementation performed at the internal socket layer. To turn on encryption, set the configuration variable AGS_SOCKET_ENCRYPT to "1" (on, true, yes). It must be set before any socket communication is performed. It cannot be changed via a SET ENVIRONMENT statement.

For more information about AGS_SOCKET_COMPRESS and AGS_SOCKET_ENCRYPT, see section 6.3.1, "Configuring the Remote Application Runtime," in the AcuConnect User's Guide.

filename_VERSION

The value of filename_VERSION is now set to "5" by default. Filename_VERSION allows you to specify the Vision file format of a particular file. (Filename is replaced by the name of the target file.) When this variable is set to "5", the file is created and treated as a Vision 5 file. The values "2", "3", and "4" specify their respective Vision file formats. Any other value causes the default value to be used.

TC_CONTINUITY_WINDOW

The GetMessage API routine behaves differently under Windows 2000 and Windows XP than it does in prior versions of Windows. If an application has no open windows and it calls GetMessage, the focus is transferred to another application. Once the focus is transferred, the application cannot force the focus to return to the original application, even if it subsequently creates a window to receive the focus. This situation arises in thin client environments if the COBOL application destroys all of its windows before creating a new one. This can result in the application losing the focus under Windows 2000/XP.

You can work around this situation by ensuring that at least one window remains open in the application at all times. This window can be invisible. A new configuration variable, TC_CONTINUITY_WINDOW, automates this process in thin client environments. For more information about TC_CONTINUITY_WINDOW, see Appendix H of Book 4, ACUCOBOL-GT Appendices.

TC_DELAY_ACTIVATE

In Version 5.2.1 of the thin client, CMD-ACTIVATE events were delayed until after the Windows notification that caused the event was complete. This was done to prevent a problem where a program that did not honor CMD-ACTIVATE events could get into a loop if it tried to activate a different window instead. This variable makes that delay optional. If you find that clicking on another window in your application causes the thin client to hang or crash, set TC_DELAY_ACTIVATE to "1" (on, true, yes) to delay CMD-ACTIVATE events. The default for this variable is "0" (off, false, no).

TC_TV_SELCHANGING

This variable is designed for thin client applications. It provides some control over when the runtime generates MSG-TV-SELCHANGING events for tree view controls. Because most applications that use tree view controls do not process MSG-TV-SELCHANGING events, the thin client now suppresses its generation in some cases. This improves both performance and stability. For more information, see the entry for TC_TV_SELCHANGING in Appendix H of Book 4, ACUCOBOL-GT Appendices.

USE_LARGE_FILE_API

On UNIX systems, this variable allows you to turn on or off file system API support for very large files (files greater than 2 gigabytes). USE_LARGE_FILE_API is set to "1" (on, yes, true) by default. This setting enables support for large files. However, some UNIX systems don't support files greater than 2 gigabytes and setting USE_LARGE_FILE_API to "0" (off, false, no) tells the runtime to use the standard, 32-bit file system API. This variable has no effect on Windows systems. See Appendix H in Book 4, ACUCOBOL-GT Appendices, for more information.

V_INDEX_BLOCK_PERCENT

This variable can be used to specify index pre-allocate and extension factors as a percentage of the factors applied to the data segment. A more detailed description of V_INDEX_BLOCK_PERCENT is included in the section titled "Larger pre-allocate and extension factors," a subsection of "Vision Version 5." See Appendix H in Book 4, ACUCOBOL-GT Appendices, for more information.

V_BASENAME_TRANSLATION

This variable allows you to tell Vision whether to include full path information in the filename (rather than just the base name). A more detailed description of V_BASENAME_TRANSLATION is given in the section titled "Expanded control over Vision filename translation," a subsection of "Vision Version 5."

V_STRIP_DOT_EXTENSION

This variable allows you to direct Vision to retain the "dot extension" in the filename. A more detailed description of V_STRIP_DOT_EXTENSION is included in the section titled "Ability to retain the "dot" extension in the filename," a subsection of "Additional Enhancements to Vision."

V52_BITMAPS

This variable determines whether your application uses device-dependent or device-independent bitmaps for image processing. You may set the runtime to exclusively use device-independent or device-dependent code, or to apply the code dynamically, based on the program's object semantics. See the entry for V52_BITMAPS in Appendix H of Book 4, ACUCOBOL-GT Appendices.

V60_LIST_VALUE

This variable allows you to specify which search algorithm the runtime will use to match the specified value in a list box or combo box. A complete description of this issue is included in the section titled "Setting the VALUE in a List Box or Combo Box."

V_VERSION

Beginning with Version 6.0, V_VERSION has a default value of "5", which causes new Vision files to be created in the Vision 5 format. If V_VERSION is set to "2", "3", or "4", Vision files are created in the corresponding Vision format. Any other value causes the default value to be used.