xref: /freebsd/lib/libkvm/kvm_geterr.3 (revision 1da7f3f6f72b2245e458fc7195733268ae4a1136)
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32.Dd March 21, 2017
33.Dt KVM_GETERR 3
34.Os
35.Sh NAME
36.Nm kvm_geterr
37.Nd get error message on kvm descriptor
38.Sh LIBRARY
39.Lb libkvm
40.Sh SYNOPSIS
41.In kvm.h
42.Ft char *
43.Fn kvm_geterr "kvm_t *kd"
44.Sh DESCRIPTION
45This function returns a string describing the most recent error condition
46on the descriptor
47.Fa kd .
48The results are undefined if the most recent
49.Xr kvm 3
50library call did not produce an error.
51The string returned is stored in memory owned by
52.Xr kvm 3
53so the message should be copied out and saved elsewhere if necessary.
54.Sh RETURN VALUES
55The function
56.Fn kvm_geterr
57will return "" if
58.Fa kd
59is
60.Dv NULL
61or an error has not been captured for
62.Fa kd .
63.Sh SEE ALSO
64.Xr kvm 3 ,
65.Xr kvm_close 3 ,
66.Xr kvm_getargv 3 ,
67.Xr kvm_getenvv 3 ,
68.Xr kvm_getprocs 3 ,
69.Xr kvm_nlist 3 ,
70.Xr kvm_open 3 ,
71.Xr kvm_openfiles 3 ,
72.Xr kvm_read 3 ,
73.Xr kvm_write 3
74.Sh BUGS
75This routine cannot be used to access error conditions due to a failed
76.Fn kvm_openfiles
77call, since failure is indicated by returning a
78.Dv NULL
79descriptor.
80Therefore, errors on open are output to the special error buffer
81passed to
82.Fn kvm_openfiles .
83This option is not available to
84.Fn kvm_open .
85