const crypto = require("crypto");
crypto.pbkdf2("secret", "salt", 1024, 32, "sha512", function (err, derivedKey) {
if (err) throw err;
console.log(derivedKey.toString("hex"));
});
// 8177086d9bc2e39580a7657fabe06e685a57b861768a36406c5744711f461e49
for example, the length of the final output above is 64, why it is not the value of keylen. What exactly is the length of keylen here?