function Deno.open
open(path: string | URL,options?: OpenOptions,): Promise<FsFile>
Open a file and resolve to an instance of [`Deno.FsFile`](../././~/Deno.FsFile). The
file does not need to previously exist if using the `create` or `createNew`
open options. The caller may have the resulting file automatically closed
by the runtime once it's out of scope by declaring the file variable with
the `using` keyword.
```ts
using file = await Deno.open("/foo/bar.txt", { read: true, write: true });
// Do work with file
```
Alternatively, the caller may manually close the resource when finished with
it.
```ts
const file = await Deno.open("/foo/bar.txt", { read: true, write: true });
// Do work with file
file.close();
```
Requires `allow-read` and/or `allow-write` permissions depending on
options.
optional
options: OpenOptions
Promise<FsFile>