let ptr1 = sys.malloc(1024)
let ptr2 = sys.malloc(4321)
println(`ptr: ${ptr1} ${ptr2}; used mem: ${sys.getUsedMem()}`)
println(`freeing ptr1`)
sys.free(ptr1)
println(`used mem now: ${sys.getUsedMem()}`)
println(`freeing ptr2`)
sys.free(ptr2)
println(`used mem now: ${sys.getUsedMem()}`)