1.\"
2.\" Copyright (c) 1992 The Regents of the University of California
3.\" Copyright (c) 1990, 1992 Jan-Simon Pendry
4.\" All rights reserved.
5.\"
6.\" This code is derived from software donated to Berkeley by
7.\" Jan-Simon Pendry.
8.\"
9.\" %sccs.include.redist.roff%
10.\"
11.\"	@(#)mount_kernfs.8	5.2 (Berkeley) 07/19/92
12.\"
13.\"
14.Dd
15.Dt MOUNT_KERNFS 8
16.Os BSD 4.4
17.Sh NAME
18.Nm mount_kernfs
19.Nd mount the /kern file system
20.Sh SYNOPSIS
21.Nm mount_kernfs
22.Op Fl F Ar fsoptions
23.Pa /kern
24.Pa mount_point
25.Sh DESCRIPTION
26The
27.Nm mount_kern
28command attaches an instance of the kernel parameter
29namespace to the global filesystem namespace.
30The conventional mount point is
31.Pa /kern .
32This command is normally executed by
33.Xr mount 8
34at boot time.
35.Pp
36The filesystem includes several regular files which can be read,
37some of which can also be written.
38The contents of the files is in a machine-independent format,
39either a string, or an integer in decimal ASCII.
40Where numbers are returned, a trailing newline character is also added.
41.Sh FILES
42.Bl -tag -width copyright -compact
43.It Pa boottime
44the time at which the system was last booted (decimal ASCII).
45.It Pa copyright
46kernel copyright message.
47.It Pa hostname
48the hostname, with a trailing newline.
49The hostname can be changed by writing to this file.
50A trailing newline will be stripped from the hostname being written.
51.It Pa hz
52the frequency of the system clock (decimal ASCII).
53.It Pa loadavg
54the 1, 5 and 15 minute load average in kernel fixed-point format.
55The final integer is the fix-point scaling factor.
56All numbers are in decimal ASCII.
57.It Pa pagesize
58the machine pagesize (decimal ASCII).
59.It Pa physmem
60the number of pages of physical memory in the machine (decimal ASCII).
61.It Pa root
62the system root directory.
63In a chroot'ed environment,
64.Nm
65can be used to create a new
66.Pa /kern
67mount point.
68.Pa /kern/root
69will then refer to the system global root, not the current process root.
70.It Pa rootdev
71the root device.
72.It Pa rrootdev
73the raw root device.
74.It Pa time
75the second and microsecond value of the system clock.
76Both numbers are in decimal ASCII.
77.It Pa version
78the kernel version string.
79The head line for
80.Pa /etc/motd
81can be generated by running:
82.Dq Ic "sed 1q /kern/version"
83.El
84.Sh SEE ALSO
85.Xr mount 2 ,
86.Xr unmount 2 ,
87.Xr fstab 5
88.Sh CAVEATS
89This filesystem may not be NFS-exported.
90.Sh HISTORY
91The
92.Nm
93filesystem
94is
95.Ud
96