fs

Reading

fs.readFile('file.txt', function(err, data) { .. });
fs.readFile('file.txt', {encoding: 'utf-8'}, function(err, data) { .. });

Writing

fs.writeFile('output.txt', function(err) { .. });
fs.appendFile('output.txt', function(err) { .. });

Watch

fs.watch('dir OR file.txt', { persistent: true }, function(event, file) {
  event; /* rename | change */
});

Getting info

fs.exists('file.txt', function(exists /*bool*/) { ... });

fs.stat('file.txt', function(stats) {
  stats.isFile();
  stats.isDirectory();
  stats.isSymbolicLink();
});

File operations

fs.rename('old.txt', 'new.txt', function(){});
fs.chown('file.txt', uid, gid, function(){});
fs.symlink('src', 'dest', function(){});
fs.unlink('path', function(){});
fs.rmdir('path', function(){});

fs.readdir('path', function(err, files) { .. }); /* `files` = array of names */

Path

fs.realpath('/etc/passwd', function(err, path) { /* "/private/etc/passwd" */ });

Sync

data = fs.readFileSync('input.txt');
fs.writeFileSync('output.txt', data);
fs.appendFileSync('output.txt', data);
fs.existsSync('file.txt');

References

• https://nodejs.org/api/fs.html