Comments by "Toby" (@toby9999) on "why do void* pointers even exist?" video.

  1. Yeah, that's generally not a good idea. A pointer should be initialised to memory or the address of an object such as an int variable, etc..
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  2. To deal with memory addresses. C was very broadly speaking and conceptually a higher level assembler. The next step up in a way. Memory address are fundamental in assembly language because we're dealing with the cpu and other hardware items directly, hence memory addresses in assembly and pointers in C.
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  3. The heap manager or whatever the implementation uses will store that information during the allocation in something like a header area.
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  4. That information is typically stored as overhead in a header area or some such. Could be implementation specific. It's 15 years since I had to deal with that stuff but yes, the system knows how much memory was allocated for each.
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  5. What you said about %d is correct, but in this example, he is not printing a pointer anyway.
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  6. Not really.
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  7. C is a language designed to get close to the hardware level. Memory addresses are effectively void* on the CPU. It makes sense. For those who want a higher level abstraction, C is the wrong tool.
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  8. That would be a useless video.
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  9. Strictly speaking it's not part of the type per se. The declaration consists of two components conceptually... e.g. int x,*y; The 'int' declares the data storage type to be 'int'. The * says y is a ponter.
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  10. A memory address with no type.
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  11. Unlike C++, the C language does not provide for pass by reference. In order to have a function modify an object or variable passed in (such as person), one has to pass a pointer. That pointer will be dereferenced by the function with operator -> The other reason for passing a pointer would be for efficiency.
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