Single user mode

Unix family

In OS X El Capitan and later releases of macOS, a userspace reboot to single-user mode can be performed with the command sudo launchctl reboot userspace -s in Terminal, and the system can be fully rebooted in single-user mode with the command sudo launchctl reboot system -s. On macOS High Sierra and earlier versions, a user can also enter single user mode by holding down ⌘ S at startup, which may require entering a password set in the firmware. Single-user mode is different from safe mode in that the system goes directly to the console instead of starting up the core elements of macOS (items in /System/Library/, ignoring /Library/, ~/Library/, et al.). From there users are encouraged by a prompt to run fsck or other command line utilities as needed (or installed).