08-04-2009
Since UNIX covers so many platforms and systems and varieties its hard to give a better than vague answer. But I will bite the bullet and be vague for you.
- The system automatically loads the bootloader. This is a small program with only one job, to find and load the operating system kernel. On PC's its always in the first sector of the hard drive, or the 'boot' sector.
- The bootloader loads the kernel into memory and runs it.
- In linux at least, the first thing the kernel does is detect a whole slew of system parameters and devices. This is similar to the process of loading a driver, except the drivers are built in and just need to be operated.
- Next, it attempts to mount the root filesystem, since it can't do anything without one.
- Lastly the kernel creates process number one, init, which runs the processes to prepare the rest of the system and start up all the services its is configured to for its particular runlevel, including all terminal logins etc.
This is the simple way. Sometimes instead of a root filesystem, the bootloader gives the kernel a glob of memory containing files loaded from disk, which it may use to load extra drivers etc. before it mounts the real root filesystem overtop of it.
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SPLASHY(1) Splashy POSIX boot splash system SPLASHY(1)
NAME
Splashy - a user-mode, POSIX and LSB compliant, boot splashing system for UNIX.
SYNOPSIS
splashy { boot | shutdown | test | preview }
splashy_chvt { TTY_NUMBER }
DESCRIPTION
Splashy displays an image and a progress bar at boot time. When called as splashy_chvt, it allows the same functionality as the UNIX
command chvt.
OPTIONS
boot Does boot sequence. See EXAMPLES.
shutdown
Does shutdown sequence. See EXAMPLES.
test, preview
Use to test splashy without having to reboot the system. this shows a progressbar continuously moving as well as the current image
for the currently selected theme. See EXAMPLES.
EXAMPLES
"/sbin/splashy test"
Used to test splashy. Useful for testing new themes.
"/sbin/splashy boot"
Used when booting your system. This is run automatically by a initrc script during boot.
"/sbin/splashy shutdown"
Similar in spirit to boot, but run during shutdown. This is run automatically by a initrc script during shutdown.
FILES
/etc/splashy/config.xml
Main configuration. defines how splashy should be setup.
/etc/splashy/themes/default/config.xml
Default theme. defines how the images displayed by splashy should be setup, their location and other theme-related variables.
NOTES
To use splashy as chvt, make a symbolic link from splashy's location to a new path. i.e.: cd /sbin; ln -s splashy splashy_chvt
SEE ALSO
splashy_config(1), splashy_update(1), splashy-config.xml(5), splashy-theme.xml(5)
AUTHORS
Luis Mondesi <lemsx1@gmail.com>
perl v5.12.1 2010-07-05 SPLASHY(1)