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[www.bnp.org.uk]

Hi

I am writing a program in C and need to know how I can directly access say 1mb of memory allocated via malloc.

Within this 1mb I need to be able to read and write individual bytes and words.

Prototype: void *malloc(size_t size);

malloc returns a pointer of type void, which is a pointer that points to anything i.e. it doesn't have a type like char, short int, int etc. Apparently it is not possible to get a value at the address of a void pointer presumably because it is not known what type that value would be.

So how do I read and write bytes (chars) and words (short ints)?

Regards

[tedius]

You will have to cast the point first. You should then be able to use it as normal.

[www.bnp.org.uk]

Thanks. I have been reading up on pointers via google and understand what you have typed.

So now that I have *pChar, can I point it anywhere inside this allocated memory, say for example pChar = pChar + 0x100 and then *pChar = 0xff?

I want access to the memory as you would get in assembler.

Cheers.

[tedius]

Yes, you can move the pointer to any point in you allocated space to read write. But you must be careful that you don't end up going off the end of memory that you have allocated.

[Gordon]

Because that would cause a segmentation fault, your program would immediately quit and, depending on how your system is set up, would produce a core dump to help with tracing the problem.
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