mirror of
https://github.com/freebsd/freebsd-src
synced 2024-09-06 17:18:32 +00:00
93 lines
3.2 KiB
Groff
93 lines
3.2 KiB
Groff
![]() |
.\" Copyright (c) 1992, 1993
|
||
|
.\" The Regents of the University of California. All rights reserved.
|
||
|
.\"
|
||
|
.\" This code is derived from software developed by the Computer Systems
|
||
|
.\" Engineering group at Lawrence Berkeley Laboratory under DARPA contract
|
||
|
.\" BG 91-66 and contributed to Berkeley.
|
||
|
.\"
|
||
|
.\" 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.
|
||
|
.\"
|
||
|
.\" 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.
|
||
|
.\"
|
||
|
.\" @(#)kvm_read.3 8.1 (Berkeley) 6/4/93
|
||
|
.\"
|
||
|
.Dd June 4, 1993
|
||
|
.Dt KVM_READ 3
|
||
|
.Os
|
||
|
.Sh NAME
|
||
|
.Nm kvm_read ,
|
||
|
.Nm kvm_write
|
||
|
.Nd read or write kernel virtual memory
|
||
|
.Sh SYNOPSIS
|
||
|
.Fd #include <kvm.h>
|
||
|
.Ft ssize_t
|
||
|
.Fn kvm_read "kvm_t *kd" "u_long addr" "void *buf" "size_t nbytes"
|
||
|
.Ft ssize_t
|
||
|
.Fn kvm_write "kvm_t *kd" "u_long addr" "const void *buf" "size_t nbytes"
|
||
|
.Sh DESCRIPTION
|
||
|
The
|
||
|
.Fn kvm_read
|
||
|
and
|
||
|
.Fn kvm_write
|
||
|
functions are used to read and write kernel virtual memory (or a crash
|
||
|
dump file). See
|
||
|
.Fn kvm_open 3
|
||
|
or
|
||
|
.Fn kvm_openfiles 3
|
||
|
for information regarding opening kernel virtual memory and crash dumps.
|
||
|
.Pp
|
||
|
The
|
||
|
.Fn kvm_read
|
||
|
function transfers
|
||
|
.Fa nbytes
|
||
|
bytes of data from
|
||
|
the kernel space address
|
||
|
.Fa addr
|
||
|
to
|
||
|
.Fa buf .
|
||
|
Conversely,
|
||
|
.Fn kvm_write
|
||
|
transfers data from
|
||
|
.Fa buf
|
||
|
to
|
||
|
.Fa addr .
|
||
|
Unlike their SunOS counterparts, these functions cannot be used to
|
||
|
read or write process address spaces.
|
||
|
.Sh RETURN VALUES
|
||
|
Upon success, the number of bytes actually transferred is returned.
|
||
|
Otherwise, -1 is returned.
|
||
|
.Sh SEE ALSO
|
||
|
.Xr kvm 3 ,
|
||
|
.Xr kvm_close 3 ,
|
||
|
.Xr kvm_getargv 3 ,
|
||
|
.Xr kvm_getenvv 3 ,
|
||
|
.Xr kvm_geterr 3 ,
|
||
|
.Xr kvm_getprocs 3 ,
|
||
|
.Xr kvm_nlist 3 ,
|
||
|
.Xr kvm_open 3 ,
|
||
|
.Xr kvm_openfiles 3
|