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If a const is just a pointer to a variable that isn't allowed to be changed ... is there any reason I couldn't take the address of that pointer, assign it to another (non-const) variable, and change the const's value that way?
The compiler won't let you take the address of a CONST variable and assign it to something. (You can use it in a comparison, such as to check if it's *NULL, but when the parm is CONST, it won't let you store the output of %addr() into a variable.)
midrange.com
// this code is legal:
if %addr(ConstParm) = *NULL;
// this code is not:
ptr = %addr(ConstParm);
It is possible to TRICK the compiler, such as when you use a prototype
that doesn't match the procedure interface, or when you go outside the
scope of the subprocedure to get the address from the caller. In those
cases it is, in fact, possible to change the value of a CONST parameter.
But, that's going pretty far out of your way when you could've just left the "CONST" off of the prototype in the first place.
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