Updated December 2023; see History
xcall SWPSBR, function {,parameters dependent on function}
SWPSBR performs various functions related to the Swap multi-session and screen-tracking system available as a third-party add-on in the AMOS world. A-Shell does not support Swap per se, since it has its own screen tracking system (TRACKER) and multi-session system (either PolyShell or using multiple Windows instances), but it does support most of the SWPSBR functions, which are listed below. Note that unless you already have a lot of code using these functions, you would be better off to use MSBOXX, which can do all of these things and which is both more powerful and better supported.
xcall SWPSBR, 0, active$
Function 0 tests whether the Swap system is active. A-Shell returns "Y" in the active$ parameter.
xcall SWPSBR, 1, screen
xcall SWPSBR, 1, srow, scol, erow, ecol, screen
Function 1 restores the previously saved window or entire screen. With Swap, the screen parameter was a buffer to hold the screen contents, but it is ignored with A-Shell, which has an internal storage scheme. (You can map it as X,1 to save space.) However, A-Shell's scheme acts like a stack, so you must save and restore in LIFO order (i.e. last item saved will be the first item restored.) The first format above restores the entire screen. The second format restores a previously saved partial screen.
You can also restore an entire screen with Tab(-1,203), assuming it has previously been saved with Tab(-1,202) or an equivalent. You can also save and restore partial screens using MSBOXX
xcall SWPSBR, 3, screen
xcall SWPSBR, 3, srow, scol, erow, ecol, screen
Function 3 saves an entire screen (first format) or partial screen (second format). See Function 1 above for the restore operation.
xcall SWPSBR, 7, srow, scol, erow, ecol, siz
Function 7 was used to establish the size needed to store the specified screen area. The call is simply ignored by A-Shell, since you do not need to provide any storage space for the save and restore operations.
xcall SWPSBR, 8, srow, scol, erow, ecol
Function 8 was used to restore attributes on the right side of the box. It is not implemented by A-Shell. You do not need this capability with mode emulations (such as Windows, VT100, etc.) and if you really need it, you can get it by using MSBOXX and the BOX_FAO option, or via Function 128.
xcall SWPSBR, 9, srow, scol, erow, ecol
Function 9 clears the specified box. It is equivalent to the MSBOXX option BOX_ERA.
xcall SWPSBR, 128, srow, scol, erow, ecol, flags
Function 128 draws a box, with various options determined by the contents of the flags parameter. The options are listed in the following table, and may be strung together using commas. For example, "T,C,B,O=2,I=3."
Flags |
Description |
|---|---|
B |
Draw a border around the box. Equivalent to MSBOXX option BOX_BDR. |
C |
Clear interior of box. Equivalent to MSBOXX option BOX_ERA. |
T |
Seal up field attributes. Equivalent to MSBOXX option BOX_FAO. |
I=<text fg> |
Sets the text (interior) foreground color. For example, I=1 would set it to white. Equivalent to the IBOX'FG parameter in MSBOXX. |
O=<border fg> |
Sets the border (outside) foreground color. For example, O=2 would set it to color 2 (blue). Equivalent to the BRDR'FG parameter in MSBOXX. |
xcall SWPSBR, 129, screen, fspec$
Function 129 saves the current screen, VUEs the specified file, then restores the screen. As with the other functions involving the Screen parameter, Screen is ignored by A-Shell, which instead uses EZTYP to save the screen, display the file, and restore the screen on exit.
History
2023 November, A-Shell 7.0.1751.4: Hot spots created with Tab(-1,162) are now saved and restored in ATE environments as well as pure Windows. Note however that in the ATE environment, the application needs to send a Tab() command with an explicit termination following the Tab(-1,162) in order to get a clean save/restore. Tab(-1,254); (flush) is the simplest way to satisfy the requirement.
