# C.call

Bind through the cache and invoke immediately.

```js
client.call(symbol, signature, ...args)
```

## Arguments

| Argument | Type | Meaning |
| --- | --- | --- |
| `symbol` | string | Exported symbol. |
| `signature` | object | Required returns and args (array of fixed type names). Optional library (absolute executable path), ownership (borrowed/retained for object results), captureErrno (boolean). |
| `args` | any | Arguments matching signature.args. |

## Returns

Converted native result; with captureErrno:true, {value, errno}.

## Example

```js
console.log(C.call("strlen", {returns: "size_t", args: ["cstring"]}, "Hello"));
```

## Notes

Advanced API: the declared types must match the real native function. Wrong signatures/addresses can crash the target. No variadic functions, callbacks or arbitrary custom structures. Calls run on the target main thread. See [C functions and memory](/doc/native) for types and ownership.

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