nthline
Version:
read nth line without reading entire file
34 lines (23 loc) • 1.12 kB
Markdown
# node-nthline [](https://travis-ci.org/BorisChumichev/node-nthline) [](https://coveralls.io/github/BorisChumichev/node-nthline)
`nthline` reads specific line from file without buffering the entire file to memory. Under the hood it uses Node’s [readline](https://nodejs.org/api/readline.html) module.
### Install
```
npm i -S nthline
```
### Usage
Module exposes just one function: `nthline` with signature: `(rowIndex:Number, filePath:String) → Promise`. Row indexing is zero-based.
```javascript
;(async () => {
const nthline = require('nthline'),
filePath = '/path/to/100-million-rows-file',
rowIndex = 42
console.log(await nthline(rowIndex, filePath))
})()
```
Since it returns a promise you could rewrite previous example like that:
```javascript
const nthline = require('nthline'),
filePath = '/path/to/100-million-rows-file',
rowIndex = 42
nthline(rowIndex, filePath).then(line => console.log(line))
```