Hello,
I've never had a basic course on memory or architecture (in any language) and I find myself needing clarification on basic concepts relating to memory (allocation, usage, etc.) and architecture, preferably using AS400 as the base. Concepts such as the different types of memory allocations (static, dynamic, etc), the different types of memory (buffers, stack, heap, segments, cache), the size of the blocks of memory used in AS400, etc.
I need to understand exactly where in the memory data is stored when a READ is done (what kind of memory), or when I write to a subfile, or when I want to use the key word RTNDTA on a DSPF. Why a subprocedure can "see" and use global variables but why the main program can't use the variables of a subprocedure (what mechanism prevents this?). When is memory allocated? When is it released? How does a variable identify which memory space to work on (for example, when a subprocedure has a local variable with the same name as a global variable, how does it know to work on the local variable instead of the global?).
A basic course explaining the basics of memory and architecture in respect to AS400. Everytime I do a search, I only ever come across the concepts of memory pools. I'm not there yet!
Thanks!
I've never had a basic course on memory or architecture (in any language) and I find myself needing clarification on basic concepts relating to memory (allocation, usage, etc.) and architecture, preferably using AS400 as the base. Concepts such as the different types of memory allocations (static, dynamic, etc), the different types of memory (buffers, stack, heap, segments, cache), the size of the blocks of memory used in AS400, etc.
I need to understand exactly where in the memory data is stored when a READ is done (what kind of memory), or when I write to a subfile, or when I want to use the key word RTNDTA on a DSPF. Why a subprocedure can "see" and use global variables but why the main program can't use the variables of a subprocedure (what mechanism prevents this?). When is memory allocated? When is it released? How does a variable identify which memory space to work on (for example, when a subprocedure has a local variable with the same name as a global variable, how does it know to work on the local variable instead of the global?).
A basic course explaining the basics of memory and architecture in respect to AS400. Everytime I do a search, I only ever come across the concepts of memory pools. I'm not there yet!
Thanks!
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