xref: /freebsd/lib/libkvm/kvm_geterr.3 (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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32.\"     @(#)kvm_geterr.3	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD$
34.\"
35.Dd March 21, 2017
36.Dt KVM_GETERR 3
37.Os
38.Sh NAME
39.Nm kvm_geterr
40.Nd get error message on kvm descriptor
41.Sh LIBRARY
42.Lb libkvm
43.Sh SYNOPSIS
44.In kvm.h
45.Ft char *
46.Fn kvm_geterr "kvm_t *kd"
47.Sh DESCRIPTION
48This function returns a string describing the most recent error condition
49on the descriptor
50.Fa kd .
51The results are undefined if the most recent
52.Xr kvm 3
53library call did not produce an error.
54The string returned is stored in memory owned by
55.Xr kvm 3
56so the message should be copied out and saved elsewhere if necessary.
57.Sh RETURN VALUES
58The function
59.Fn kvm_geterr
60will return "" if
61.Fa kd
62is
63.Dv NULL
64or an error has not been captured for
65.Fa kd .
66.Sh SEE ALSO
67.Xr kvm 3 ,
68.Xr kvm_close 3 ,
69.Xr kvm_getargv 3 ,
70.Xr kvm_getenvv 3 ,
71.Xr kvm_getprocs 3 ,
72.Xr kvm_nlist 3 ,
73.Xr kvm_open 3 ,
74.Xr kvm_openfiles 3 ,
75.Xr kvm_read 3 ,
76.Xr kvm_write 3
77.Sh BUGS
78This routine cannot be used to access error conditions due to a failed
79.Fn kvm_openfiles
80call, since failure is indicated by returning a
81.Dv NULL
82descriptor.
83Therefore, errors on open are output to the special error buffer
84passed to
85.Fn kvm_openfiles .
86This option is not available to
87.Fn kvm_open .
88