Some friends cannot install Apple developer tools command line tools，When installing, it will prompt "The software cannot be installed.，Because it is currently unavailable from the software update server"，Let me teach you how to install it manually。 What are command line tools? Command Line Tools is a small standalone package from Apple，Available for macOS，Expanded the terminal with additional functionality。including but not limited to：svn、git、make、GCC、clang、perl、size、strip、strings、libtool、cpp、what、codesign and others...

When using a Mac computer，for safety，Many users will set an administrator password。If you accidentally forget your Mac administrator password，don’t worry，Here are a few ways you can reset your password and restore access。 未开启FileVault的用户 方法一：使用Apple ID重置 在OS X Mavericks（10.9）及其后续版本中，Apple integrates Apple ID and administrator password，Allow quick reset of user password using Apple ID。Please make sure your Mac is logged in with Apple ID，And check "Allow users to reset passwords using Apple ID" in "System Preferences - Users & Groups - Sign-in Options"..