gistfile1.ts

const { permissions, revokePermission, open } = Deno;
const encoder = new TextEncoder();

const logPromise = open('request.log', 'a+');

// Revoke all permissions
const perms = permissions();
for (const perm in perms) {
  if (perms[perm]) {
    console.log('revoked '+perm);
    revokePermission(perm as any);
  }
} 
console.log(permissions());

(async () => {
  const logfile = await logPromise;
  await logfile.write(encoder.encode("hello\n"));
  
  await open('some other file', 'a+');
})();