dan@Apple.COM (Dan Allen) (05/27/88)
There is a limit to the amount of global data that can be referenced in the current Mac OS. I realize that this is a problem. I have mentioned before that USUALLY when people need to work with lots of real numbers, as in large global numeric arrays, there are very slick ways of allocating the data and getting around the conformant array problem. I have previously mentioned that a very good solution for the C programming language can be found in "Numerical Receipes in C", Cambridge Press. I agree that in the best of all possible worlds there would not be any global data limit. But there is a limit currently. I am simply saying that to change it right now would cause a lot of incompatibility problems, and that there are useful and easy workarounds to the problem. I also said that the average large Mac application does not have a problem, and I quoted the following data: HyperCard 1.2 312732 bytes of code, 25872 bytes of global data = 8% MPW Shell 2.0+ 179874 bytes of code, 20674 bytes of global data = 11% Let's all live with the limit, knowing that in some future Mac OS we will certainly try to have the problem fixed. Let's spend our time in the meantime trying to write good code and not moan about this problem so much... Dan Allen Software Explorer Apple Computer
dan@Apple.COM (Dan Allen) (06/08/88)
OK, OK. So everyone wants global data. I wish I could give you megabytes worth. My comments have been mainly trying to help people work around a known problem. I have suggested that in some instances, global arrays can be allocated dynamically on the heap without much problem. I have suggested that in the case of large arrays in numerics applications that doing so can bring other advantages, especially in C. I have also suggested ways of working around the initialized data problems that seem to arise with yacc, lex, flex, and bison. These problems can be worked around by the use of Rez, for example. I realize that the 32K global data problem is a problem. I hope that Apple can solve the problem, but unfortunately I am not in any group currently that has the charter to do so. I will, however, pass on the general conscensus of the net that this problem should be fixed. I hope you will understand that we at Apple are sympathetic to this problem. I hope that I have not sounded like I did not think there was a problem. Thank you for your support. Dan Allen Software Explorer Apple Computer