NAME

kernel − UNIX system executable file containing basic operating system services

SYNOPSIS

/kernel/unix [ −abrsv ]

DESCRIPTION

The operating system image, or kernel, is the collection of software made up of the core image file (/kernel/unix) and all of the modules loaded at any instant in time.  The system will not function without a kernel to control it. 

The kernel is loaded by the boot(1M) command in a machine-specific way.  The kernel may be loaded from disk or CD-ROM ("diskfull boot") or over the network ("diskless boot").  In either case, the directories under /kernel must be readable and must contain executable code which is able to perform the required kernel service.  If the −a flag is given, the user is able to supply different pathnames for the default locations of the kernel and modules. 

The ’moddir’() variable specifies a path list that the kernel searches for modules. ­’moddir’() can be set in the /etc/system file; it defaults to /kernel:/usr/kernel. 

The kernel configuration can be controlled using the /etc/system file (see system(4)). 

OPTIONS

−a Ask the user for configuration information, such as where to find the system file, where to mount root, and even override the name of the kernel itself.  Default responses will be contained in square brackets ([]), and the user may simply enter Return to use the default response (note that Return is labeled Enter on some kyboards).  /dev/null may be entered at the prompt which asks for the pathname of the system configuration file.  See system(4). 

−b Do not run bcheckrc(1M). 

−r Reconfiguration boot.  The system will probe all attached hardware devices and assign nodes in the file system to represent only those devices actually found.  It will also configure the logical namespace in /dev as well as the physical namespace in /devices. 

−s Boot only to init level ’s’.  See init(1M). 

−v Boot with verbose messages enabled.  If this flag is not given, the messages are still printed, but the output is directed to the system logfile.  See syslogd(1M). 

EXAMPLES

To boot in single-user interactive mode, use one of the following:

>b −as

>b /kernel/unix −as

DIAGNOSTICS

The kernel gives various warnings and error messages.  If the kernel detects an unrecoverable fault, it will panic or halt. 

FILES

/kernel/unix statically loadable portion of the kernel

/kernel/drv loadable device drivers

/kernel/exec modules used to exec processes

/kernel/fs file system modules

/kernel/misc miscellaneous system-related modules

/kernel/sched operating system schedulers

/kernel/strmod System V STREAMS loadable modules

/kernel/sys loadable system calls

/etc/system system configuration file

/usr/kernel common directory for loadable kernel modules

BUGS

Bugs in the kernel often result in kernel panics. 

SEE ALSO

boot(1M), kadb(1M), savecore(1M), system(4)

SunOS 5.1  —  Last change: 31 May 1993