Re: OT: Requesting C advice

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Matthew Saltzman wrote:

It will definitely print *something*. The question is, can you guarantee what it will print.
In C89, no in C99, yes.

It's not addressed directly in the FAQ, but I believe it's possible to prove that (unsigned) -2 must be the two's complement representation of -2 in however many bits make up an int. I know there was some controversy about that when the standard was being developed. In any case, I don't know of any modern machine that doesn't represent negative integers in two's complement.
Reach into your pocket, and pull out your calculator.

[snip]

sizeof(char) == 1 is guaranteed by the standard. There's no reference
to "bytes", but it is commonly accepted that the char type is a byte.
Erm, from the Standard:

3.4
       [#1] byte
       addressable  unit  of  data storage large enough to hold any
       member  of  the  basic  character  set  of   the   execution
       environment

It's possible to have chars that are not eight bits, but I can't think of a modern machine that does that. There were some old machines (Honeywells?) that had six-bit bytes and 36-bit words.
All this is based on my recollection of discussions in comp.lang.c and
comp.std.c when the standard was under development.
Mike
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