小编Nol*_*ang的帖子

我在运行时收到此错误anchor deploy：

Deploying workspace: http://127.0.0.1:8899
Upgrade authority: /home/<user>/.config/solana/id.json
Deploying program "faucet"...
Program path: /home/<user>/Workspace/<project_path>/target/deploy/xxx.so...
Error: RPC request error: cluster version query failed: error sending request for url (http://127.0.0.1:8899/): error trying to connect: tcp connect error: Connection refused (os error 111)
There was a problem deploying: Output { status: ExitStatus(ExitStatus(256)), stdout: "", stderr: "" }.

在部署之前，我已经运行以下命令来更改本地的集群配置：

Deploying workspace: http://127.0.0.1:8899
Upgrade authority: /home/<user>/.config/solana/id.json
Deploying program "faucet"...
Program path: /home/<user>/Workspace/<project_path>/target/deploy/xxx.so...
Error: RPC request error: cluster version query failed: error sending request …

我的问题是：

1. 种子是什么？
2. 为什么需要种子？
3. 种子输入是随机的还是特定的？

举些例子：

1. 第一个参数是函数的种子findProgramAddress

const [_pda, _nonce] = await PublicKey.findProgramAddress(
  [Buffer.from(anchor.utils.bytes.utf8.encode("escrow"))],
  program.programId
)

2. 第二个参数是函数 createWithSeed 的种子？

const GREETING_SEED = 'hello';
const greetedPubkey = await PublicKey.createWithSeed(
  payer.publicKey,
  GREETING_SEED,
  programId,
);

struct User {
    username: String,
    email: String,
    sign_in_count: u64,
    active: bool,
}

fn main() {
    let mut user = User {
        username: String::from("Paulx"),
        email: String::from("paulx@gmail.io"),
        sign_in_count: 0,
        active: true,
    };

    let name = user.username;
    user.username = String::from("Alix");

    println!("{}", name);
}

您将看到 是username从用户复制的变量name。变量name不是标量类型，为什么它可以复制呢？