Function callback

test/parallel/test-fs-link.js:14–18

(err)

fs.writeFileSync(srcPath, 'hello world');

function callback(err) {
  assert.ifError(err);
  const dstContent = fs.readFileSync(dstPath, 'utf8');
  assert.strictEqual(dstContent, 'hello world');
}

fs.link(srcPath, dstPath, common.mustCall(callback));