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Diffstat (limited to 'freebsd-userspace/lib/libkvm/kvm.3')
| -rw-r--r-- | freebsd-userspace/lib/libkvm/kvm.3 | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/freebsd-userspace/lib/libkvm/kvm.3 b/freebsd-userspace/lib/libkvm/kvm.3 new file mode 100644 index 00000000..9dcd772d --- /dev/null +++ b/freebsd-userspace/lib/libkvm/kvm.3 @@ -0,0 +1,120 @@ +.\" 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. +.\" 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.3 8.1 (Berkeley) 6/4/93 +.\" $FreeBSD$ +.\" +.Dd April 25, 2010 +.Dt KVM 3 +.Os +.Sh NAME +.Nm kvm +.Nd kernel memory interface +.Sh LIBRARY +.Lb libkvm +.Sh DESCRIPTION +The +.Nm +library provides a uniform interface for accessing kernel virtual memory +images, including live systems and crash dumps. +Access to live systems is via +.Xr sysctl 3 +for some functions, and +.Xr mem 4 +and +.Xr kmem 4 +for other functions, +while crash dumps can be examined via the core file generated by +.Xr savecore 8 . +The interface behaves similarly in both cases. +Memory can be read and written, kernel symbol addresses can be +looked up efficiently, and information about user processes can +be gathered. +.Pp +The +.Fn kvm_open +function is first called to obtain a descriptor for all subsequent calls. +.Sh COMPATIBILITY +The kvm interface was first introduced in SunOS. +A considerable +number of programs have been developed that use this interface, +making backward compatibility highly desirable. +In most respects, the Sun kvm interface is consistent and clean. +Accordingly, the generic portion of the interface (i.e., +.Fn kvm_open , +.Fn kvm_close , +.Fn kvm_read , +.Fn kvm_write , +and +.Fn kvm_nlist ) +has been incorporated into the +.Bx +interface. +Indeed, many kvm +applications (i.e., debuggers and statistical monitors) use only +this subset of the interface. +.Pp +The process interface was not kept. +This is not a portability +issue since any code that manipulates processes is inherently +machine dependent. +.Pp +Finally, the Sun kvm error reporting semantics are poorly defined. +The library can be configured either to print errors to +.Dv stderr +automatically, +or to print no error messages at all. +In the latter case, the nature of the error cannot be determined. +To overcome this, the +.Bx +interface includes a +routine, +.Xr kvm_geterr 3 , +to return (not print out) the error message +corresponding to the most recent error condition on the +given descriptor. +.Sh SEE ALSO +.Xr kvm_close 3 , +.Xr kvm_getargv 3 , +.Xr kvm_getenvv 3 , +.Xr kvm_geterr 3 , +.Xr kvm_getfiles 3 , +.Xr kvm_getloadavg 3 , +.Xr kvm_getprocs 3 , +.Xr kvm_getswapinfo 3 , +.Xr kvm_nlist 3 , +.Xr kvm_open 3 , +.Xr kvm_openfiles 3 , +.Xr kvm_read 3 , +.Xr kvm_write 3 , +.Xr sysctl 3 , +.Xr kmem 4 , +.Xr mem 4 |