How to know actual size of byte buffer`s content in nodejs?

node.js buffer
lor1an picture lor1an · Aug 18, 2016 · Viewed 30.6k times · Source

I get files as byte buffers and cannot use fs.stat() method. So I am try to use buf.length but this length refers to the amount of memory allocated for the buffer object and not actually the content size. For example I have file with with size 22,449 bytes. buf.length returns for 39804 for it.

Answer

stdob-- picture stdob-- · Aug 18, 2016

You need byteLength:

var buff = fs.readFileSync(__dirname + '/test.txt');
console.log(Buffer.byteLength(buff));

For node 0.10.21 you can try this:

console.log(buff.toString().length);

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