HLSL varying variable alternative

How would I go about passing values calculated in the vertex shader to the pixel shader?
Whats HLSL's alternative to GLSL's varying variable?

as a texcoord

*cough*
Could someone give me a simple example of, let's say passing a single float value from the VS to the PS.

*vomit over face*

Maybe you could just, you know, not use a proprietary language and use GLSL instead.

My circumstances require I use HLSL.

Anyway I got that passing a variable thing down, though I've come across a new problem.
I'm calculating the dot product for the normal vector and light direction, however the result is always zero (or something, idk).

...
void main (in float3 norm : NORMAL0,...) {
...
float3 light = {1,1,1};
float x = dot(light,norm);
...
}

^ Is that technically correct?

may I suggest you a lesser forum for this task? /prog/ is only for discussing better languages like LISP and brainfuck.
try gamedev