Node.JS WriteFile - File of specific size

Question

Is there a way to specify the size/length of a file and have the system reserve the space needed? I'm looking for something like:

fs.write('file', Buffer, 1024*1024*54); // To create 54MB file.

Answer 1

Just create a Buffer of that size?

fs.writeFile('file', new Buffer(1024*1024*54));