When the Open Firmware startup program in BootROM locates and selects the Mac OS X operating system, it transfers control to BootX (a process that Open Firmware starts from /System/Library/CoreServices on the startup disk). The primary task of BootX is to initialize the kernel environment and the drivers (such as the drivers for I/O buses) needed to boot the system. In addition, BootX starts up the kernel initialization process. When Open Firmware attempts to find BootX, one of the following icons will appear, indicating these results:
MORE INFO Refer to Knowledge Base document 58042, "A flashing question mark appears when you start your Mac." If Mac OS X components have been renamed or moved from the root level of the startup disk, a broken folder icon will appear. A black belt may appear around a folder icon if a Mac OS 9 restore has been installed incorrectly using the Restore discs that came with the computer. MORE INFO Refer to Knowledge Base document 106294, "Mac OS X: Reinstalling Mac OS 9 or recovering from a software restore." When loading the kernel environment, BootX first attempts to load a previously cached set of device drivers. If this cache is missing or corrupt, BootX searches /System/Library/Extensions for drivers and other kernel extensions whose OSBundleRequired property is set to the appropriate value for the type of boot. (This is either a local or network boot, depending upon the current selection in Startup Disk preferences.) You can recognize this stage by the metallic Apple logo and the spinning gear that appear on the screen. |