Hello, Menjras
Wellcome to our board.
Unfortunately we don't speak Arabic, but we can try to talk in English.
The use of overlays (real mode only) looks like a good solution to solve the problem related to low memory in older machines when you're using RTLink or even an ancient version of BLinker. But the most modern solution is to create a program to work in protected mode. And it's possible even in ancient versions of BLinker. The result is fantastic and your program can continue growing up without any problem. By the way you will notice your program running faster and with no memory swaps or any other disk access.
This special way of execution forces your program to run in the extended memory area (above the first 1MB). Naturally, your operating system needs to load in boot-time a special memory management driver. In pure DOS it's mandatory in config.sys. Of course, work in pure DOS is a deprecated way to work. So, I'll forget this and I'll talk considering you're using Windows in (not)NT-kernel (95/98/Me/2K/XP). In this case, don't worry about that driver. Automatically it's available by your OS when you open a new DOS session.
If you're interested in this special running mode, the good new is: there are only 2 basic steps to follow. Let's see:
1) The BLinker needs to know what is your intention. Insert the command BLINKER EXECUTABLE EXTENDED in your linkage script to activate the protected mode.
2) Include a special library to permit BLinker to work appropriately with the many special features envolved in protected mode (and many new functions). What library depends what is your version of the Clipper. Basically there are only 2 options:
LIBRARY BLXCLP52 ---> version 5.2x
LIBRARY BLXCLP53 ---> version 5.3x
Pay attention to the unique possible bad new. Some libraries are not prepared to run in protect mode. What this means? Some libraries make direct memory access (like video RAM) and this is not allowed. Remember: the name is "protected mode". So, the memory is protected and any memory access needs an OS authorization through an element called "memory selector". Ancient libraries, many times, makes direct access. Therefore, running in protected mode, when the program tries to access directly a protected memory area, it always triggers a GPS (General Protection Fault) and crashes.
Download the BLinker 7 (last version), install it and study its help. You will note many interesting features (commands and functions) that will help you to work in a much better way. By the way, I want to detach two interesting functions: BliCPURel() that reduce the CPU consumption and SwpRunCmd() that substitute (much) more efficiently the RUN command.
I hope this message helps you to see more clearly how this execution mode works and which benefits you could gain. Despite some few inconveniences with one or another ancient library, this is the preferred mode to work by 9 of each 10 Clipper programmers.
One more time: be wellcome. Feel free to talk us in any language you want. Except arabic, of course.
