xref: /freebsd/lib/libkvm/kvm_geterr.3 (revision c6989859ae9388eeb46a24fe88f9b8d07101c710)
1.\" Copyright (c) 1992, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" This code is derived from software developed by the Computer Systems
5.\" Engineering group at Lawrence Berkeley Laboratory under DARPA contract
6.\" BG 91-66 and contributed to Berkeley.
7.\"
8.\" Redistribution and use in source and binary forms, with or without
9.\" modification, are permitted provided that the following conditions
10.\" are met:
11.\" 1. Redistributions of source code must retain the above copyright
12.\"    notice, this list of conditions and the following disclaimer.
13.\" 2. Redistributions in binary form must reproduce the above copyright
14.\"    notice, this list of conditions and the following disclaimer in the
15.\"    documentation and/or other materials provided with the distribution.
16.\" 3. Neither the name of the University nor the names of its contributors
17.\"    may be used to endorse or promote products derived from this software
18.\"    without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
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