function main() {
let file = os.open("output.txt", "w+")
let bytes = file.puts("Hello", " ", "World", "!")
Log("Bytes written:", bytes) // Bytes written: 12
file.seek(0, 0)
let data = file.read()
Log("data:", data) // If using os.open("output.txt", "w") may result in data being undefined
// data: Hello World!
// file.puts() // error: puts requires at least 1 argument at main
file.puts(", Hello YouQuant!")
file.seek(0, 0)
data = file.read()
Log("data:", data) // data: Hello World!, Hello YouQuant!
file.close()
}