binary numbers

Tim Roberts timr at
Thu Oct 7 07:25:51 CEST 2004

Brad Tilley <bradtilley at> wrote:
>I Forgot that I'm asking a bunch of CS geeks a 
>question about "binary"... I mean "bianry" as in 
>the base 2 representation of numbers... One is one 
>is one, but one can be represented in different 
>bases and still be one... get it?

Not inside a computer, it can't.

>Dec	Bin
>1		1
>2		10
>3		11
>4		100
>5		101
>6		110
>How do I pass the binary representation of a 
>number to a function???

I'm afraid that it is YOU that does not understand.

Binary is the ONLY representation used inside a computer.  When you see the
number "5", it is because a utility function has neatly converted the
binary value in a variable or register to an ASCII format that your human
brain can comprehend.  ALL of the following things are equivalent:

   x = 15
   x = 037
   x = 0x0f
   x = 6+9
   x = len("abcdefghijklmno")

In every case, the variable "x" will contain the binary value 000..0000101,
again because a utility function has neatly converted the human-convenient
forms above into a binary value.

The registry type REG_BINARY does not really mean binary.  It means an
arbitrary array of bytes.  The only difference between REG_BINARY and
REG_SZ is that a REG_BINARY value can contain zeros, and is displayed
differently in a registry dump.
- Tim Roberts, timr at
  Providenza & Boekelheide, Inc.

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