xref: /freebsd/lib/libkvm/kvm_kerndisp.3 (revision fa9012aef1ad596a99950f986cf1fb31111c034a)
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25.\" $FreeBSD$
26.\"
27.Dd February 5, 2020
28.Dt KVM_KERNDISP 3
29.Os
30.Sh NAME
31.Nm kvm_kerndisp
32.Nd get kernel displacement
33.Sh LIBRARY
34.Lb libkvm
35.Sh SYNOPSIS
36.In kvm.h
37.Ft kssize_t
38.Fn kvm_kerndisp "kvm_t *kd"
39.Sh DESCRIPTION
40.Fn kvm_kerndisp
41returns the number of bytes by which the kernel referenced by
42.Fa kd
43is displaced.
44This is the difference between the kernel's base virtual address at run time
45and the kernel base virtual address specified in the kernel image file.
46.Pp
47Note that if the kernel is moved to a lower memory address,
48the displacement will be negative.
49.Sh RETURN VALUES
50.Fn kvm_kerndisp
51returns the number of bytes by which the kernel is displaced.
52If the kernel is not displaced or if it is not possible to find the
53displacement then 0 is returned.
54.Sh SEE ALSO
55.Xr kvm 3 ,
56.Xr kvm_close 3 ,
57.Xr kvm_open 3
58