kvm_geterr.3

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.\"     @(#)kvm_geterr.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD$
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.Dd March 21, 2017
.Dt KVM_GETERR 3
.Os
.Sh NAME
.Nm kvm_geterr
.Nd get error message on kvm descriptor
.Sh LIBRARY
.Lb libkvm
.Sh SYNOPSIS
.In kvm.h
.Ft char *
.Fn kvm_geterr "kvm_t *kd"
.Sh DESCRIPTION
This function returns a string describing the most recent error condition
on the descriptor
.Fa kd .
The results are undefined if the most recent
.Xr kvm 3
library call did not produce an error.
The string returned is stored in memory owned by
.Xr kvm 3
so the message should be copied out and saved elsewhere if necessary.
.Sh RETURN VALUES
The function
.Fn kvm_geterr
will return "" if
.Fa kd
is
.Dv NULL
or an error has not been captured for
.Fa kd .
.Sh SEE ALSO
.Xr kvm 3 ,
.Xr kvm_close 3 ,
.Xr kvm_getargv 3 ,
.Xr kvm_getenvv 3 ,
.Xr kvm_getprocs 3 ,
.Xr kvm_nlist 3 ,
.Xr kvm_open 3 ,
.Xr kvm_openfiles 3 ,
.Xr kvm_read 3 ,
.Xr kvm_write 3
.Sh BUGS
This routine cannot be used to access error conditions due to a failed
.Fn kvm_openfiles
call, since failure is indicated by returning a
.Dv NULL
descriptor.
Therefore, errors on open are output to the special error buffer
passed to
.Fn kvm_openfiles .
This option is not available to
.Fn kvm_open .