KVM_KREAD(3KVM) Kernel VM Library Functions KVM_KREAD(3KVM)
NAME
kvm_kread, kvm_kwrite, kvm_uread, kvm_uwrite - copy data to or from a
kernel image or running system
SYNOPSIS
cc [
flag... ]
file...
-lkvm [
library...]
#include <kvm.h>
ssize_t kvm_kread(
kvm_t *kd,
uintptr_t addr,
void *buf,
size_t nbytes);
ssize_t kvm_kwrite(
kvm_t *kd,
uintptr_t addr,
void *buf,
size_t nbytes);
ssize_t kvm_uread(
kvm_t *kd,
uintptr_t addr,
void *buf,
size_t nbytes);
ssize_t kvm_uwrite(
kvm_t *kd,
uintptr_t addr,
void *buf,
size_t nbytes);
DESCRIPTION
The
kvm_kread() function transfers data from the kernel address space
to the address space of the process.
nbytes bytes of data are copied
from the kernel virtual address given by
addr to the buffer pointed
to by
buf.
The
kvm_kwrite() function is like
kvm_kread(), except that the
direction of the transfer is reversed. To use this function, the
kvm_open(3KVM) call that returned
kd must have specified write
access.
The
kvm_uread() function transfers data from the address space of the
processes specified in the most recent
kvm_getu(3KVM) call.
nbytes bytes of data are copied from the user virtual address given by
addr to the buffer pointed to by
buf.
The
kvm_uwrite() function is like
kvm_uread(), except that the
direction of the transfer is reversed. To use this function, the
kvm_open(3KVM) call that returned
kd must have specified write
access. The address is resolved in the address space of the process
specified in the most recent
kvm_getu(3KVM) call.
RETURN VALUES
On success, these functions return the number of bytes actually
transferred. On failure, they return -1.
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Stable |
+--------------------+-----------------+
|MT-Level | Unsafe |
+--------------------+-----------------+
SEE ALSO
kvm_getu(3KVM),
kvm_nlist(3KVM),
kvm_open(3KVM),
attributes(7) May 2, 2002 KVM_KREAD(3KVM)
