On 9/18/21 5:40 AM, frame wrote:
On Friday, 17 September 2021 at 14:29:23 UTC, Steven Schveighoffer wrote:
Looking at that signature, it does not appear that it uses
zero-termination at all, as it takes a length. So using `dup` and
therefore the gc is totally unnecessary.
I'm assuming that string is the barcode argument?
No, the string appears inside the C-function. I'm calling the function
with .ptr and the .length property as it expects.
Oh wow, I totally misunderstood what you are doing. I thought you were
*calling* that function, but you are *reimplementing* that code in D.
Have you tried:
```d
const(char)* s2 = "...";
```
This will work because string literals are zero terminated and
implicitly castable to `immutable(char)*`, which will also implicitly
cast to `const(char)*`.
That should allow s2 to be reassigned but not modify the data. IIRC,
string literal data even in C is put into a read-only section by many
compilers, so the code shouldn't be changing it.
Now that I understand what you are doing, it becomes clear that this
isn't a situation of C code being called. Or are you calling other parts
of the C library with that translated function?
The first rule of porting -- just translate, don't change anything. I
would try to do exactly what C does without using the GC at all.
Continue to use malloc/free. If you have issues with type
representation, you may need to adjust for that.
-Steve
