How to use the ftruncateSync function from fs

fs.js

GitHub: blockcollider/bcnode

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exports.fstat = co.promisify(fs.fstat);
exports.fstatSync = fs.fstatSync;
exports.fsync = co.promisify(fs.fsync);
exports.fsyncSync = fs.fsyncSync;
exports.ftruncate = co.promisify(fs.ftruncate);
exports.ftruncateSync = fs.ftruncateSync;
exports.futimes = co.promisify(fs.futimes);
exports.futimesSync = fs.futimesSync;
exports.lchmod = co.promisify(fs.lchmod);
exports.lchmodSync = fs.lchmodSync;

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test-fs-error-messages.js

GitHub: nwjs/node

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  common.runWithInvalidFD((fd) => {
    fs.ftruncate(fd, 4, common.mustCall(validateError));


    assert.throws(
      () => fs.ftruncateSync(fd, 4),
      validateError
    );
  });
}

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test-fs-truncate.js

GitHub: vladimir-andreevich/node.js-14-windows-7

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{
  const file2 = path.resolve(tmp, 'truncate-file-2.txt');
  fs.writeFileSync(file2, 'Hi');
  const fd = fs.openSync(file2, 'r+');
  process.on('beforeExit', () => fs.closeSync(fd));
  fs.ftruncateSync(fd, 4);
  assert(fs.readFileSync(file2).equals(Buffer.from('Hi\u0000\u0000')));
}


{

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+ 2 other calls in file

index.js

GitHub: vladimir-andreevich/node.js-14-windows-7

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  });
}


function createZeroFilledFile(filename) {
  const fd = fs.openSync(filename, 'w');
  fs.ftruncateSync(fd, 10 * 1024 * 1024);
  fs.closeSync(fd);
}

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test-fs-largefile.js

GitHub: Mike7323/Mike-s-construction

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const filepath = path.join(tmpdir.path, 'large.txt');
const fd = fs.openSync(filepath, 'w+');
const offset = 5 * 1024 * 1024 * 1024; // 5GB
const message = 'Large File';

fs.ftruncateSync(fd, offset);
assert.strictEqual(fs.statSync(filepath).size, offset);
const writeBuf = Buffer.from(message);
fs.writeSync(fd, writeBuf, 0, writeBuf.length, offset);
const readBuf = Buffer.allocUnsafe(writeBuf.length);

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