xref: /freebsd/lib/libkvm/kvm_nlist.3 (revision e716630d4cf89e69ec3f675ebfceee09f1a85e05)
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32.\"     @(#)kvm_nlist.3	8.1 (Berkeley) 6/4/93
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34.Dd November 27, 2015
35.Dt KVM_NLIST 3
36.Os
37.Sh NAME
38.Nm kvm_nlist ,
39.Nm kvm_nlist2
40.Nd retrieve symbol table names from a kernel image
41.Sh LIBRARY
42.Lb libkvm
43.Sh SYNOPSIS
44.In kvm.h
45.In nlist.h
46.Ft int
47.Fn kvm_nlist "kvm_t *kd" "struct nlist *nl"
48.Ft int
49.Fn kvm_nlist2 "kvm_t *kd" "struct kvm_nlist *nl"
50.Sh DESCRIPTION
51The
52.Fn kvm_nlist
53function retrieves the symbol table entries indicated by the name list argument
54.Fa \&nl .
55This argument points to an array of nlist structures, terminated by
56an entry whose
57.Fa n_name
58field is
59.Dv NULL
60(see
61.Xr nlist 3 ) .
62Each symbol is looked up using the
63.Fa n_name
64field, and if found, the
65corresponding
66.Fa n_type
67and
68.Fa n_value
69fields are filled in.
70These fields are set
71to 0 if the symbol is not found.
72.Pp
73The
74.Xr kldsym 2
75system call is used to locate symbols in live kernels.
76This is a less than perfect
77emulation of the nlist values but has the advantage of being aware of kernel
78modules and is reasonably fast.
79.Pp
80The
81.Fn kvm_nlist2
82function retrieves the symbol table entries indicated by the name list argument
83.Fa nl .
84This argument points to an array of
85.Vt "struct kvm_nlist"
86structures,
87terminated by an entry whose
88.Fa n_name
89field is
90.Dv NULL
91These structures are similar to the nlist structures used by
92.Fn kvm_nlist
93except that the
94.Fa n_value
95field uses a different type
96.Pq Vt kvaddr_t
97to avoid truncation when examining non-native kernel images.
98.Sh RETURN VALUES
99The
100.Fn kvm_nlist
101and
102.Fn kvm_nlist2
103functions return the number of invalid entries found.
104If the kernel symbol table was unreadable, -1 is returned.
105.Sh SEE ALSO
106.Xr kldsym 2 ,
107.Xr kvm 3 ,
108.Xr kvm_close 3 ,
109.Xr kvm_getargv 3 ,
110.Xr kvm_getenvv 3 ,
111.Xr kvm_geterr 3 ,
112.Xr kvm_getprocs 3 ,
113.Xr kvm_native 3 ,
114.Xr kvm_open 3 ,
115.Xr kvm_openfiles 3 ,
116.Xr kvm_read 3 ,
117.Xr kvm_write 3
118.Sh HISTORY
119The
120.Fn kvm_nlist2
121function first appeared in
122.Fx 11.0 .
123