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36 .\" @(#)kvm_read.3 8.1 (Berkeley) 6/4/93
37 .\" $FreeBSD: src/lib/libkvm/kvm_read.3,v 1.6.2.3 2001/12/17 10:08:30 ru Exp $
38 .\" $DragonFly: src/lib/libkvm/kvm_read.3,v 1.4 2008/09/07 08:36:54 swildner Exp $
47 .Nd read or write kernel virtual memory
54 .Fn kvm_read "kvm_t *kd" "unsigned long addr" "void *buf" "size_t nbytes"
56 .Fn kvm_readstr "kvm_t *kd" "unsigned long addr" "char *buf" "size_t *len"
58 .Fn kvm_write "kvm_t *kd" "unsigned long addr" "const void *buf" "size_t nbytes"
65 functions are used to read and write kernel virtual memory (or a crash
70 for information regarding opening kernel virtual memory and crash dumps.
77 the kernel space address
87 Unlike their SunOS counterparts, these functions cannot be used to
88 read or write process address spaces.
92 function exists for convenience to read NUL terminated strings
93 from the kernel address space.
99 will allocate a sufficiently large buffer, which needs to be
108 will interpret the value it is pointing to as the size of
110 and will store the size of the complete string at
114 is too small to hold the complete string,
126 the number of bytes actually transferred is returned, if the request
128 Otherwise, -1 is returned.
133 is returned on failure.
134 Upon success, the address of the string is returned, which will be
136 if this was supplied.