onexit()

```javascript
function main(){
    Log("开始运行, 5秒后停止，并执行扫尾函数！")
    Sleep(1000 * 5)
}

// 扫尾函数实现
function onexit(){
    var beginTime = new Date().getTime()
    while(true){
        var nowTime = new Date().getTime()
        Log("程序停止倒计时..扫尾开始，已经过去：", (nowTime - beginTime) / 1000, "秒！")
        Sleep(1000)
    }
}

import time 
def main():
    Log("开始运行, 5秒后停止，并执行扫尾函数！")
    Sleep(1000 * 5)

def onexit():
    beginTime = time.time() * 1000
    while True:
        ts = time.time() * 1000
        Log("程序停止倒计时..扫尾开始，已经过去：", (ts - beginTime) / 1000, "秒！")
        Sleep(1000)

void main() {
    Log("开始运行, 5秒后停止，并执行扫尾函数！");
    Sleep(1000 * 5);
}

void onexit() {
    auto beginTime = Unix() * 1000;
    while(true) {
        auto ts = Unix() * 1000;
        Log("程序停止倒计时..扫尾开始，已经过去：", (ts - beginTime) / 1000, "秒！");
        Sleep(1000);
    }
}

测试onexit()函数：

function main() {
    if (exchange.GetName().startsWith("Futures_")) {
        Log("交易所为期货")
        exchange.SetContractType("swap")
    } else {
        Log("交易所为现货")
    }

    if (IsVirtual()) { 
        try { 
            onTick()
        } catch (e) { 
            Log("error:", e)
        }  
    } else {
        onTick()
    }
}

function onTick() {
    while (true) {
        var ticker = exchange.GetTicker() 
        LogStatus(_D(), ticker ? ticker.Last : "--")
        Sleep(500) 
    } 
}

function onexit() { 
    Log("执行扫尾函数") 
}

def main():
    if exchange.GetName().startswith("Futures_"):
        Log("交易所为期货")
    else:
        Log("交易所为现货")

    if IsVirtual():
        try:
            onTick()
        except Exception as e:
            Log(e)
    else:
        onTick()

def onTick():
    while True:
        ticker = exchange.GetTicker()
        LogStatus(_D(), ticker["Last"] if ticker else "--")
        Sleep(500)

def onexit():
    Log("执行扫尾函数")

#include <iostream>
#include <exception>
#include <string>

void onTick() {
    while (true) {
        auto ticker = exchange.GetTicker();
        LogStatus(_D(), ticker);
        Sleep(500);
    } 
}

void main() {
    std::string prefix = "Futures_";
    bool startsWith = exchange.GetName().substr(0, prefix.length()) == prefix;
    if (startsWith) {
        Log("交易所为期货");
        exchange.SetContractType("swap");
    } else {
        Log("交易所为现货");
    }

    if (IsVirtual()) {
        try {
            onTick();
        } catch (...) {
            std::cerr << "Caught unknown exception" << std::endl;
        }        
    } else {
        onTick();
    }
}

void onexit() { 
    Log("执行扫尾函数");
}

由于回测系统中策略通常设计为一个死循环不停轮询执行，会导致在回测系统中无法触发执行策略中实现的onexit()函数。可以通过检测回测系统结束标记（EOF异常）来触发onexit()函数执行。

回测系统 init()