method Deno.FsFile.prototype.write
FsFile.prototype.write(p: Uint8Array): Promise<number>
Write the contents of the array buffer (`p`) to the file.
Resolves to the number of bytes written.
**It is not guaranteed that the full buffer will be written in a single
call.**
```ts
const encoder = new TextEncoder();
const data = encoder.encode("Hello world");
using file = await Deno.open("/foo/bar.txt", { write: true });
const bytesWritten = await file.write(data); // 11
```
Promise<number>