Pointers are more abstract than you might expect in C

By Stefan Schulze Frielinghaus

A pointer references a location in memory and dereferencing a pointer refers to the lookup of the value of the memory location the pointer references. The value of a pointer is a memory address. The C standard does not define the representation of a memory address. This is crucial since not every architecture makes use of the same memory addressing paradigm. Most modern architectures make use of a linear address space or something similar. Still, even this is not precise enough since you might want to talk about physical or virtual addresses. Some architectures make even use of non-numeric addresses. For example, the Symbolics Lisp Machine makes use of tuples of the form (object, offset) as addresses.

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Fun and Bugs in Microsoft Word 1.1a

The Microsoft company made a present to all programmers eager to dig into some interesting stuff: they opened the source codes of MS-DOS v 1.1, v 2.0 and Word for Windows 1.1a. The MS-DOS operating system is written in an assembler, so the analyzer cannot be applied to it. But Word is written in C. Word 1.1a’s source codes are almost 25 years old, but we still managed to analyze it. There’s no practical use of it, of course. Just for fun.


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