@guaju fatal: unable to access 'https://mirrors.ustc.edu.cn/homebrew-core.git/': Operation timed out after 300024 milliseconds with 0 out of 0 bytes received
Error: Fetching /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core failed!
==> Downloading https://homebrew.bintray.com/bottles-portable-ruby/portable-ruby--2.6.3.mavericks.bottle.tar.gz
Already downloaded: /Users/mac/Library/Caches/Homebrew/portable-ruby--2.6.3.mavericks.bottle.tar.gz
Error: Checksum mismatch.
Expected: ab81211a2052ccaa6d050741c433b728d0641523d8742eef23a5b450811e5104
Actual: cdbb0f8f0173b0c1ce9b0dcdc6bd8f49f99a95b9252980b4594375302de8687f
Archive: /Users/mac/Library/Caches/Homebrew/portable-ruby--2.6.3.mavericks.bottle.tar.gz
To retry an incomplete download, remove the file above.
Error: Failed to install vendor Ruby.
2019-01-04 mac使用brew update无反应,更新慢解决办法主要是资源访问太慢的原因造成的，替换一下镜像就可以了 有点耐心，大概5分钟就可以了，刚开始的时候terminal 只有顶部的title栏会变化，最后才会出现更新结果 使用中科...