Read all text from stdin to a string

node.js stdin synchronous
rwallace picture rwallace · May 25, 2015 · Viewed 12.6k times · Source

I'm writing a program in Node.js that (in some situations) wants to act as a simple filter: read everything from stdin (up to end of file), do some processing, write the result to stdout.

How do you do the 'read everything from stdin' part? The closest solutions I've found so far, seem to work either for one line at a time from the console, or else only work when stdin is a file not a pipe.

Answer

Patrick Narkinsky picture Patrick Narkinsky · May 6, 2019

My boiler-plate for this one is a lot like the solution described in a comment above -- offering it at the top level because it's very much the simplest way to do this and it shouldn't be only in a comment.

var fs = require('fs');
var data = fs.readFileSync(0, 'utf-8');
// Data now points to a buffer containing the file's contents

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