Contributor: SWAG SUPPORT TEAM TITLE: TURBO PASCAL MEMORY ISSUES =========================================================== TP 4.0 5.0 5.5 EXEC - SETTING HEAP MEMORY Q. How do I set the heap memory when executing a child process? A. Probably the best way to do this is through trial and error. Set the heap maximum to some large value, and run the program. If it runs out of memory, then divide the maximum by 2, and so on, until the parent and child programs have enough memory. The same can be done with the heap minimum. Also, if you have access to CompuServe, you can download a routine that swaps the parent program between memory and disk. TP 4.0 5.0 5.5 - ALLOCATING AND RECLAIMING MEMORY USING DOS Q. What Dos functions can I use to reclaim memory to Dos? A. You essentially must write your own GetMem and FreeMem routines. GetMem would make a call to Dos function $48 and FreeMem would make a call to Dos function $49. For more details on these functions please consult an IBM PC programmer's guide. TP 4.0 5.0 5.5 - MEMORY CONTROL BLOCKS Q. How many memory control blocks does a Turbo Pascal program use? A. Just one. TP 5.0 5.5 - EMS SUPPORT Q. Does Turbo Pascal 5.0+ support EMS? A. Yes. Turbo Pascal 5.0+ will use up to 64K (if selected in TINST) of EMS for storing the edit buffer. In addition, you can instruct the Overlay unit to place your overlaid units on EMS. Finally, EMS.PAS on the distribution disk shows you how to access EMS memory. TP 5.5 - HEAP SPACE STILL CREATED WITH HEAP MAX 0 Q. Compiling to disk with my heap maximum set to 0 still creates heap space when running .EXE file. Why? A. This has to do with the way DOS allocates memory for .EXE files in chunks of 512 bytes, rather than in chunks of 16 bytes. As a result of DOS's allocation, you always get 0-496 bytes more than you request.