How to store two file handlers in nodejs?

I need to open one file, parse it, make http requests and save the data into another file. Can I do it without nes开发者_运维知识库ting all the code in one place? (It makes code less readable.)

I'd like to have something like this in the end. Is it ok to write to global scope?

on_write_file = function(err, write_file) {
    // parse the data from the opening file
};
on_read_file = function(err, read_file) {
    fs.open('end_file', 'w', on_write_file);
};

fs.open('start_file', 'r', on_read_file);

In a web server, instead, it will be dangerous to use globals, what should I do then?

---

Yes you can, use .bind to curry data into a function.

on_write_file = function(read_file, err, write_file) {
    // parse the data from the opening file
};
on_read_file = function(err, read_file) {
    fs.open('end_file', 'w', on_write_file.bind(null, read_file));
};

fs.open('start_file', 'r', on_read_file);