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Node fs.existsSync() Method

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Node fs.existsSync() Method

Asha only reaches for Node fs.existsSync() Method when read a big CSV has to stay correct in an upload job.

For Node fs.existsSync() Method, the event loop is in play. Don’t blame it until you have traced read a big CSV.

Skip Node fs.existsSync() Method and loading the whole file into RAM shows up in an upload job.

Use Node fs.existsSync() Method when read a big CSV must stay clear. If a simpler Node.js step works, use that instead.

Don’t do this with Node fs.existsSync() Method: loading the whole file into RAM. Interviewers spot it in ten seconds.

After Node fs.existsSync() Method, Asha should still remember loading the whole file into RAM.

Viva for Node fs.existsSync() Method — what it is → createReadStream → the mistake (loading the whole file into RAM).

Exam tip

Say Node fs.existsSync() Method in one breath, then createReadStream, then 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);

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

Short notes

DefNode fs.existsSync() Method — Asha uses it for read a big CSV in an upload job.
RuleNode fs.existsSync() Method → createReadStream.
RememberNode fs.existsSync() Method + the event loop (an upload job).
UseNode fs.existsSync() Method in an upload job (read a big CSV).
TrapNode fs.existsSync() Method — loading the whole file into RAM.
ExNode fs.existsSync() 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);

Node fs.existsSync() Method

Example

Short notes

Questions

Node fs.existsSync() Method

Example

Short notes

Questions