当我升级颤振时，我遇到了以下错误消息。
curl：（56）LibreSSL SSL_read：SSL_ERROR_SYSCALL，错误54
Failed to retrieve the Dart SDK from: https://storage.googleapis.com/flutter_infra/flutter/4737fc5cd89b8f0136e927b00f2e159444b95a73/dart-sdk-darwin-x64.zip
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Flutter 1.3.8 • channel beta • https://github.com/flutter/flutter.git
Framework • revision e5b1ed7a7f (6 weeks ago) • 2019-04-11 14:01:46 -0700
Engine • revision 4737fc5cd8
Tools • Dart 2.2.1 (build 2.2.1-dev.0.0 571ea80e11)
Running flutter doctor...
Downloading Dart SDK from Flutter engine 4737fc5cd89b8f0136e927b00f2e159444b95a73...
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
这是什么？有什么问题？
errno 54是“由对等方重置连接”，其基本上表示通用网络连接问题。
在临时的wifi打嗝期间，我与flutter upgrade确实失败了。