Node.js · Theory

fs.dirent.isBlockDevice() Method

← All stacks

Theory

206/723

fs.dirent.isBlockDevice() Method

fs.dirent.isBlockDevice() Method is simple if you keep it on paper. Amit uses it for read a big CSV in an upload job.

Keep fs.dirent.isBlockDevice() Method small. Amit should finish read a big CSV in a few lines, not a 40-line dump.

fs.dirent.isBlockDevice() Method exists so Amit can keep read a big CSV correct in an upload job.

fs.dirent.isBlockDevice() Method shows up in an upload job. Name read a big CSV, not “a real-world scenario”.

fs.dirent.isBlockDevice() Method trap — loading the whole file into RAM. Amit loses marks for that every viva.

Place fs.dirent.isBlockDevice() Method next to nearby Node.js work — createReadStream is the link.

Close fs.dirent.isBlockDevice() Method with: “If I skip it, read a big CSV goes wrong like this: loading the whole file into RAM.”

Exam tip

Board: read a big CSV. Dry-run fs.dirent.isBlockDevice() Method. Name the trap: loading the whole file into RAM.

Example

const fs = require("fs");
const path = require("path");

const file = path.join(__dirname || ".", "demo.txt");
fs.writeFileSync(file, "hello node\n");
const text = fs.readFileSync(file, "utf8");
console.log(text.trim());
fs.unlinkSync(file);

fs.dirent.isBlockDevice() Method — fs reads/writes files. Prefer promises/async APIs in real apps.

Short notes

Deffs.dirent.isBlockDevice() Method — Amit uses it for read a big CSV in an upload job.
Rulefs.dirent.isBlockDevice() Method → createReadStream.
Rememberfs.dirent.isBlockDevice() Method + an Express route (an upload job).
Usefs.dirent.isBlockDevice() Method in an upload job (read a big CSV).
Trapfs.dirent.isBlockDevice() Method — loading the whole file into RAM.
Exfs.dirent.isBlockDevice() Method → read a big CSV.

const fs = require("fs"); const path = require("path"); const file = path.join(__dirname || ".", "demo.txt"); fs.writeFileSync(file, "hello node\n"); const text = fs.readFileSync(file, "utf8"); console.log(text.trim()); fs.unlinkSync(file);

fs.dirent.isBlockDevice() Method

Example

Short notes

Questions

fs.dirent.isBlockDevice() Method

Example

Short notes

Questions