.\" 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
.\" %FreeBSD: src/lib/libkvm/kvm_read.3,v 1.6.2.3 2001/12/17 10:08:30 ru Exp %
.\"
.\" $FreeBSD$
.Dd June 4, 1993
.Dt KVM_READ 3
.Os
.Sh 名称
.Nm kvm_read ,
.Nm kvm_write
.Nd カーネル仮想メモリの読取りと書込み
.Sh ライブラリ
.Lb libkvm
.Sh 書式
.In kvm.h
.Ft ssize_t
.Fn kvm_read "kvm_t *kd" "unsigned long addr" "void *buf" "size_t nbytes"
.Ft ssize_t
.Fn kvm_write "kvm_t *kd" "unsigned long addr" "const void *buf" "size_t nbytes"
.Sh 解説
.Fn kvm_read
および
.Fn kvm_write
の関数は、カーネル仮想メモリ
(またはクラッシュダンプファイル) の読取りと書込みに使用されます。
カーネル仮想メモリと
クラッシュダンプのオープンに関する情報は
.Fn kvm_open 3
または
.Fn kvm_openfiles 3
を参照してください。
.Pp
.Fn kvm_read
関数は
.Fa nbytes
バイトのデータをカーネル空間のアドレス
.Fa addr
から
.Fa buf
に転送します。逆に、
.Fn kvm_write
はデータを
.Fa buf
から
.Fa addr
に転送します。
SunOS と異なり、これらの関数は、プロセスのアドレス空間の
読取りまたは書込みに使用できません。
.Sh 戻り値
正常に終了すると、実際に転送されたバイト数が返されます。
エラー終了時は -1 が返されます。
.Sh 関連項目
.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