Answers for "failed eperm (operation not permitted) android"

EPERM: operation not permitted, open

// Example of code with error: EPERM: operation not permitted, open
try {	
  	// some code
	return res.download(`storage/${fileName}.${format}`);
} catch (e) {
	return e;
} finally {
	unlinkSync(`storage/${fileName}.${format}`);
}
// Example of code without any error:
try {
  // some code
  return res.download(`storage/${fileName}.${format}`, function (err) {
  	if (err) throw err;
    unlinkSync(`storage/${fileName}.${format}`);
  });
} catch (e) {
	return e;
}

// You can still try run the following commands in your terminal:
 npm install -g npm@latest --force
 npm update -g graceful-fs   
 npm cache clean --force