how to use the readv function from fs-extra in javascript

To use the readv function from fs-extra in JavaScript, you first need to install the package into your Node.js project using npm:

npm install fs-extra
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Then, you can require the fs-extra module and call the readv function as follows:

index.tsx
const fs = require('fs-extra');

const fd = fs.openSync('file.txt', 'r');
const buffer1 = Buffer.alloc(5);
const buffer2 = Buffer.alloc(10);
const buffers = [buffer1, buffer2];

fs.readv(fd, buffers, 0, buffers.length, 0, (err, bytesRead, buffers) => {
  if (err) {
    console.error(err);
    return;
  }

  console.log(`${bytesRead} bytes read`);
  console.log(`Buffer 1: ${buffer1.toString()}`);
  console.log(`Buffer 2: ${buffer2.toString()}`);

  fs.closeSync(fd);
});
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This code opens the file file.txt for reading, creates two buffers of sizes 5 and 10 bytes, respectively, and passes them as an array to the readv function. The function reads into each buffer in order, starting at the beginning of the array, and fills them with the contents of the file. It then executes the callback function, which logs the number of bytes read, as well as the contents of the two buffers. Finally, it closes the file descriptor using the closeSync function.