bcoin chainldb Resource Temporarily unavailable

Question

I'm trying to run a script that retrieves transactions from the blockchain. When I run the script though I get the following error:

Error: IO error: lock /home/bucko/.bcoin/testnet/chain.ldb/LOCK: Resource temporarily unavailable

Here is the JS I'm trying to run:

'use strict';

const path = require('path');
const bcoin = require('../..');
const Chain = bcoin.chain;
const Logger = bcoin.logger;
const util = bcoin.util;

const HOME = process.env.HOME;

// Setup logger to see what's Bcoin doing.
const logger = new Logger({
  level: 'debug'
});

// Create chain for testnet, specify chain directory
const chain = new Chain({
  logger: logger,
  network: 'testnet',
  db: 'leveldb',
  prefix: path.join(HOME, '.bcoin/testnet'),
  indexTX: true,
  indexAddress: true
});

(async () => {
  await logger.open();
  await chain.open();

  const entry = await chain.getEntry(50000);
  console.log('Block at 50k:', entry);

  // eslint-disable-next-line max-len
  const txhash = '7f5990b008a2d0fc006d13b15e25d05ff30fadab656d49a5c6afea0e0d0b458c';
  const txmeta = await chain.db.getMeta(util.revHex(txhash));
  console.log(`Tx with hash ${txhash}:`, txmeta);

})().catch((err) => {
  console.error(err.stack);
  process.exit(1);
});

Answer 1

You must be running testnet in another shell or some other script that has opened the chain database.

Whenever you open chain database it gets locked so only one process is in charge of it.

lsof -d txt | grep filename You could try this one to locate process holding FD for it.