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kotlinlang

Trying to call a C function (`cfg_init` from *libconfuse*) that is expecting a `CValuesRef&lt;cfg_opt_t&gt;?` as the first argument. Using the `cValuesOf` function returns `CValues&lt;CPointerVar&lt;cfg_opt_t&gt;&gt;` which doesn't match. Below is the sample code:
```
val targetStr = configString(name = "target".cstr, def = "NONE".cstr, flags = CFGF_NONE)
val end = configEnd()
val config = cfg_init(cValuesOf(targetStr, end), CFGF_NONE)
```

Below is the mapping for the C function:
```
public fun cfg_init(opts: kotlinx.cinterop.CValuesRef&lt;libconfuse.cfg_opt_t&gt;?, flags: libconfuse.cfg_flag_t /* = <http://kotlin.Int|kotlin.Int> */): kotlinx.cinterop.CPointer&lt;libconfuse.cfg_t&gt;? { /* compiled code */ }
```

Can you try to use something like this?
```
val elements = arrayOf(targetStr, end)
val opts = createValues&lt;cfg_opt_t&gt;(elements.size) { index -&gt; this.value = elements[index] }
val config = cfg_init(opts, CFGF_NONE)
```

In the second line *this.value* doesn't exist.

I have replaced the second line with the following:
```
val opts = createValues&lt;cfg_opt_t&gt;(elements.size) { pos -&gt;
        val tmp = elements[pos]
        if (tmp != null) {
            this.name = tmp.pointed.name
            this.flags = tmp.pointed.flags
        }
    }
```
Unfortunately *this.def* is read only which is a bit of a pain. Means a default value cannot be set for the first configuration option.

Is there a straightforward way in Kotlin Native to deep copy a C struct?

After running the program with the applied changes the following errors appear:
```
internal error in cfg_init_defaults(@�")
/home/napperley/battery_telemetry.conf:1: no such option 'target'
```
Looks as though the config options haven't been properly initialised.

Would be a good idea to cover the `createValues` function in the Kotlin Native documentation, for C interop in the *Passing pointers to bindings* section ( <https://github.com/JetBrains/kotlin-native/blob/master/INTEROP.md#passing-pointers-to-bindings> ).