The Boot Process of Mac OS X

The first screen you should see appear is the following with the Apple Logo:

However the complete process is as follows (as reported at OSX Book):

• Power is turned on.
• Open Firmware code is executed.
• Hardware information is collected and hardware is initialized.
• Something (usually the OS, but also things like the Apple Hardware Test, etc.) is selected to boot. The user may be prompted to select what to boot.
• Control passes to /System/Library/CoreServices/BootX, the boot loader. BootX loads the kernel and also draws the OS badges, if any.
• BootX tries to load a previously cached list of device drivers (created/updated by /usr/sbin/kextcache). Such a cache is of the type mkext and contains the info dictionaries and binary files for multiple kernel extensions. Note that if the mkext cache is corrupt or missing, BootX would look in /System/Library/Extensions for extensions that are needed in the current scenario (as determined by the value of the OSBundleRequired property in the Info.plist file of the extension's bundle.
• The init routine of the kernel is executed. The root device of the booting system is determined. At this point, Open Firmware is not accessible any more.
• Various Mach/BSD data structures are initialized by the kernel.
• The I/O Kit is initialized.
• The kernel starts /sbin/mach_init, the Mach service naming (bootstrap) daemon. mach_init maintains mappings between service names and the Mach ports that provide access to those services.

From here on, the startup becomes user-level:

• mach_init starts /sbin/init, the traditional BSD init process. init determines the runlevel, and runs /etc/rc.boot, which sets up the machine enough to run single-user.

During its execution, rc.boot and the other rc scripts source /etc/rc.common, a shell script containing utility functions, such as CheckForNetwork() (checks if the network is up), GetPID(), purgedir() (deletes directory contents only, not the structure), etc.

• rc.boot figures out the type of boot (Multi-User, Safe, CD-ROM, Network etc.). In case of a network boot (the sysctl variable kern.netboot will be set to 1 in which case), it runs /etc/rc.netboot with a start argument.

/etc/rc.netboot handles various aspects of network booting. For example, it performs network and (if any) local mounts. It also calls /usr/bin/nbst to associate a shadow file with the disk image being used as the root device. The idea is to redirect writes to the shadow file, which hopefully is on local storage.

• rc.boot figures out if a file system consistency check is required. Single-user and CD-ROM boots do not run fsck. SafeBoot always runs fsck. rc.boot handles the return status of fsck as well.
• If rc.boot exits successfully, /etc/rc, the multi-user startup script is then run. If booting from a CD-ROM, the script switches over to /etc/rc.cdrom (installation).
• /etc/rc mounts local file systems (HFS+, HFS, UFS, /dev/fd, /.vol), ensures that the directory /private/var/tmp exists, and runs /etc/rc.installer_cleanup, if one exists (left by an installer before reboot).
• /etc/rc.cleanup is run. It "cleans" a number of Unix and Mac specific directories/files.
• BootCache is started.
• Various sysctl variables are set (such as for maximum number of vnodes, System V IPC, etc.). If /etc/sysctl.conf exists (plus /etc/sysctl-macosxserver.conf on Mac OS X Server), it is read and sysctl variables contained therein are set.
• syslogd is started.
• The Mach symbol file is created.
• /etc/rc starts kextd, the daemon process that loads kernel extension on demand from kernel or client processes.
• /usr/libexec/register_mach_bootstrap_servers is run to load various Mach bootstrap based services contained in /etc/mach_init.d
• portmap and netinfo are started.
• If /System/Library/Extensions.mkext is older than /System/Library/Extensions, /etc/rc deletes the existing mkext and creates a new one. It also creates one if one doesn't exist.
• /etc/rc starts /usr/sbin/update, the daemon that flushes internal file system caches to disk frequently.
• /etc/rc starts the virtual memory system. /private/var/vm is set up as the swap directory. /sbin/dynamic_pager is started with the appropriate arguments (swap filename path template, size of swap files created, high and low water alert triggers specifying when to create additional swap files or delete existing ones).
• /etc/rc starts /usr/libexec/fix_prebinding to fix incorrectly prebound binaries.
• /etc/rc executes /etc/rc.cleanup to clean up and reset files and devices.
• /etc/rc finally launches /sbin/SystemStarter to handle startup items from locations such as /System/Library/StartupItems and /Library/StartupItems. A StartupItem is a program, usually a shell script, whose name matches the folder name. The folder contains a property list file containing key-value pairs such as Description, Provides, Requires, OrderPreference, start/stop messages etc. You can run SystemStarter -n -D as root to have the program print debugging and dependency information (without actually running anything).
• The CoreGraphics startup item starts the Apple Type Services daemon (ATSServer) as well as the Window Server (WindowServer).

By default, the loginwindow application (loginwindow.app under /System/Library/CoreServices) is executed for the console device. You can change this line in /etc/ttys if you do not want a graphical login. 

Adding new Printer to the network

To add a printer to the network, click on the plus icon at the bottom left:



Navigate to the IP window:



Enter the address of the printer you wish to add on the network, I got mine from the polytech list:

Change Paper Size

To change printing size is very easy. Currently it is set to a US standard unavailable in New Zealand:



We simply click on the menu:


And switch to A4:

Adding Peripheral Devices to an iMac

If appropriate drivers are already installed or available in the OS, it's simply plug and play.

In the case of my Android Phone, to access it's contents, I have to install "Android File Transfer":

My Phillips Earphones input by the 3.5mm jack, these don't need drivers as they are a direct output from the sound card which should already have the appropriate drivers installed.

Tethering my phone via Bluetooth took a few tries, but generally once connected worked fine.

Airdrop

Mac's connected to the same network allow you to use airdrop, which allows you to wirelessley send files to any particular person of your choosing on that same network.

Ports on an iMac

The Current Mac's normally have many ports for your use, including ample USB and Thunderbolt ports for average home usage.

Crashing a mac via Screen Sharing

As long as you know the computers name and password on the network, you can connect via screensharing. Here we connected two computers within each other and crashed two iMacs.

Connect Exchange to Mail and Calendar Apps

This is incredibly easy, simply open Mail, and navigate to the add account button on the title bar, choose which kind of account you are adding, in this instance Microsoft "Exchange", then simply enter your login details for the account. It will then prompt and ask if you wish to set this account up with other apps like Calender, tick the ones you wish, and you are done.

Migration Assisant

Migration assistant is a part of Mac OS X that allows you to migrate your data from another computer onto another one. It supports only Windows XP and later.

Making a new Network Location

In order to make a new network location, open System Preferences, and click the network icon, once in, find the location bar. Click on it to edit and add a new Location. Name it 'Classroom'. Once this is done, then renew the DCHP settings for the Ethernet Connection.

Damn Daniel, back at it again with the Wifi Issues!

Well luckily to get the wifi running in VMware, it's as simple as opening it's network preferences and enabling the Wifi as an accessable connection. The VM will however still think it's using an Ethernet connection, but don't worry, it's connected to the wifi.

How to add Software Architecture Column in Activity Monitor

When the activity monitor is opened from the Utilities Folder (or in my case the shortcut on my dock), right hand click (or alt/option click) on the blank space beside the user column. A list will appear, click on 'Kind' to tick it. A new column will now appear, you can now see which processes are 32 and 64-bit.

Which user process started first?

On my Macbook, the first user process is titled 'bird'.