BSD 4_4_Lite2 release

[unix-history] / usr / src / share / doc / psd / 05.sysman / 1.7.t

diff --git a/usr/src/share/doc/psd/05.sysman/1.7.t b/usr/src/share/doc/psd/05.sysman/1.7.t
index 0bd3506..d4653da 100644 (file)
--- a/usr/src/share/doc/psd/05.sysman/1.7.t
+++ b/usr/src/share/doc/psd/05.sysman/1.7.t
@@ -1,74 +1,188 @@
-.\" Copyright (c) 1983, 1993
+.\" Copyright (c) 1983, 1993, 1994

 .\"    The Regents of the University of California.  All rights reserved.
 .\"
 .\"    The Regents of the University of California.  All rights reserved.
 .\"

-.\" %sccs.include.redist.roff%
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"    This product includes software developed by the University of
+.\"    California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.

 .\"
 .\"

-.\"    @(#)1.7.t       8.1 (Berkeley) %G%
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.

 .\"
 .\"

-.sh "System operation support
-.PP
+.\"    @(#)1.7.t       8.4 (Berkeley) 5/26/94
+.\"
+.Sh 2 "System operation support
+.LP

 Unless noted otherwise,
 the calls in this section are permitted only to a privileged user.
 Unless noted otherwise,
 the calls in this section are permitted only to a privileged user.

-.NH 3
-Bootstrap operations
+.Sh 3 "Monitoring system operation

 .PP
 .PP

-The call
+The
+.Fn sysctl
+function allows any process to retrieve system information
+and allows processes with appropriate privileges to set system configurations.

 .DS
 .DS

-mount(blkdev, dir, ronly);
-char *blkdev, *dir; int ronly;
+.Fd sysctl 6 "get or set system information
+sysctl(name, namelen, oldp, oldlenp, newp, newlen);
+int *name; u_int namelen; result void *oldp; result size_t *oldlenp;
+void *newp; size_t newlen;

 .DE
 .DE

-extends the UNIX name space.  The \fImount\fP call specifies
-a block device \fIblkdev\fP containing a UNIX file system
-to be made available starting at \fIdir\fP.  If \fIronly\fP is
-set then the file system is read-only; writes to the file system
-will not be permitted and access times will not be updated
-when files are referenced.
-\fIDir\fP is normally a name in the root directory.
+The information available from
+.Fn sysctl
+consists of integers, strings, and tables.
+.Fn Sysctl
+returns a consistent snapshot of the data requested.
+Consistency is obtained by locking the destination
+buffer into memory so that the data may be copied out without blocking.
+Calls to
+.Fn sysctl
+are serialized to avoid deadlock.
+.PP
+The object to be interrogated or set is named
+using a ``Management Information Base'' (MIB)
+style name, listed in \fIname\fP,
+which is a \fInamelen\fP length array of integers.
+This name is from a hierarchical name space,
+with the most significant component in the first element of the array.
+It is analogous to a file pathname, but with integers as components
+rather than slash-separated strings.
+.PP
+The information is copied into the buffer specified by \fIoldp\fP.
+The size of the buffer is given by the location specified by \fIoldlenp\fP
+before the call,
+and that location is filled in with the amount of data copied after
+a successful call.
+If the amount of data available is greater
+than the size of the buffer supplied,
+the call supplies as much data as fits in the buffer provided
+and returns an error.

 .PP
 .PP

-The call
+To set a new value, \fInewp\fP
+is set to point to a buffer of length \fInewlen\fP
+from which the requested value is to be taken.
+If a new value is not to be set, \fInewp\fP
+should be set to NULL and \fInewlen\fP set to 0.
+.PP
+The top level names (those used in the first element of the \fIname\fP array)
+are defined with a CTL_ prefix in \fI<sys/sysctl.h>\fP,
+and are as follows.
+The next and subsequent levels down are found
+in the include files listed here:
+.DS
+.TS
+l l l.
+Name   Next Level Names        Description
+_
+CTL\_DEBUG     sys/sysctl.h    Debugging
+CTL\_FS        sys/sysctl.h    Filesystem
+CTL\_HW        sys/sysctl.h    Generic CPU, I/O
+CTL\_KERN      sys/sysctl.h    High kernel limits
+CTL\_MACHDEP   sys/sysctl.h    Machine dependent
+CTL\_NET       sys/socket.h    Networking
+CTL\_USER      sys/sysctl.h    User-level
+CTL\_VM        vm/vm_param.h   Virtual memory
+.TE
+.DE
+.Sh 3 "Bootstrap operations
+.LP
+The call:

 .DS
 .DS

-swapon(blkdev, size);
-char *blkdev; int size;
+.Fd mount 4 "mount a filesystem
+mount(type, dir, flags, data);
+int type; char *dir; int flags; caddr_t data;
+.DE
+extends the name space. The
+.Fn mount
+call grafts a filesystem object onto the system file tree
+at the point specified in \fIdir\fP.
+The argument \fItype\fP specifies the type of filesystem to be mounted.
+The argument \fIdata\fP describes the filesystem object to be mounted
+according to the \fItype\fP.
+The contents of the filesystem become available through the
+new mount point \fIdir\fP.
+Any files in or below \fIdir\fP at the time of a successful mount
+disappear from the name space until the filesystem is unmounted.
+The \fIflags\fP value specifies generic properties,
+such as a request to mount the filesystem read-only.
+.LP
+Information about all mounted filesystems can be obtained with the call:
+.DS
+.Fd getfsstat 3 "get list of all mounted filesystems
+getfsstat(buf, bufsize, flags);
+result struct statfs *buf; long bufsize, int flags;
+.DE
+.LP
+The call:
+.DS
+.Fd swapon 1 "add a swap device for interleaved paging/swapping
+swapon(blkdev);
+char *blkdev;

 .DE
 specifies a device to be made available for paging and swapping.
 .DE
 specifies a device to be made available for paging and swapping.

-.PP
-.NH 3
-Shutdown operations
-.PP
-The call
+.Sh 3 "Shutdown operations
+.LP
+The call:

 .DS
 .DS

-unmount(dir);
-char *dir;
+.Fd unmount 2 "dismount a filesystem
+unmount(dir, flags);
+char *dir; int flags;

 .DE
 .DE

-unmounts the file system mounted on \fIdir\fP.
-This call will succeed only if the file system is
-not currently being used.
-.PP
-The call
+unmounts the filesystem mounted on \fIdir\fP.
+This call will succeed only if the filesystem is
+not currently being used or if the MNT_FORCE flag is specified.
+.LP
+The call:

 .DS
 .DS

+.Fd sync 0 "force completion of pending disk writes (flush cache)

 sync();
 .DE
 sync();
 .DE

-schedules input/output to clean all system buffer caches.
+schedules I/O to flush all modified disk blocks resident in the kernel.

 (This call does not require privileged status.)
 (This call does not require privileged status.)

-.PP
-The call
+Files can be selectively flushed to disk using the
+.Fn fsync
+call (see section
+.Xr 2.2.6 ).
+.LP
+The call:

 .DS
 .DS

-reboot(how)
+.Fd reboot 1 "reboot system or halt processor
+reboot(how);

 int how;
 .DE
 causes a machine halt or reboot.  The call may request a reboot
 by specifying \fIhow\fP as RB_AUTOBOOT, or that the machine be halted
 int how;
 .DE
 causes a machine halt or reboot.  The call may request a reboot
 by specifying \fIhow\fP as RB_AUTOBOOT, or that the machine be halted

-with RB_HALT.  These constants are defined in \fI<sys/reboot.h>\fP.
-.NH 3
-Accounting
+with RB_HALT, among other options.
+These constants are defined in \fI<sys/reboot.h>\fP.
+.Sh 3 "Accounting

 .PP
 The system optionally keeps an accounting record in a file
 for each process that exits on the system.
 The format of this record is beyond the scope of this document.
 .PP
 The system optionally keeps an accounting record in a file
 for each process that exits on the system.
 The format of this record is beyond the scope of this document.

-The accounting may be enabled to a file \fIname\fP by doing
+The accounting may be enabled to a file \fIname\fP by doing:

 .DS
 .DS

+.Fd acct 1 "enable or disable process accounting

 acct(path);
 char *path;
 .DE
 acct(path);
 char *path;
 .DE

-If \fIpath\fP is null, then accounting is disabled.  Otherwise,
-the named file becomes the accounting file.
+If \fIpath\fP is NULL, then accounting is disabled.
+Otherwise, the named file becomes the accounting file.