Mac上python多線程錯誤：...+[__NSPlaceholderDate initialize]...

錯誤提示並且報pycharm異常退出

objc[27880]: +[__NSPlaceholderDate initialize] may have been in progress in another thread when fork() was called.
objc[27880]: +[__NSPlaceholderDate initialize] may have been in progress in another thread when fork() was called. We cannot safely call it or ignore it in the fork() child process. Crashing instead. Set a breakpoint on objc_initializeAfterForkError to debug.

剛開始以為是代碼的問題，后來才發現其實是macOS的High Sierra以上的操作系統對多線程的限制

解決辦法

1、在終端運行代碼之前  export OBJC_DISABLE_INITIALIZE_FORK_SAFETY=YES 臨時解決

2、  sudo echo "export OBJC_DISABLE_INITIALIZE_FORK_SAFETY=YES" >> ~/.bash_profile && source ~/.bash_profile 長久解決

但是這個加上去之后我寫的flask接口會報錯，導入猴子包就ok

if __name__ == "__main__":
    from gevent import monkey
    monkey.patch_all()
    app.run(debug=True, host='0.0.0.0', port=5000)

3、　打開pycharm

 

完美解決！！！！