You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: cfg_message.m
    path of file: ./repos/PsPM/src/ext/matlabbatch
    
    the code of the file until where you have to start completion: function varargout = cfg_message(varargin)

% function cfg_message(msgid, msgfmt, varargin)
% Display a message. The message identifier msgid will be looked up in a
% message database to decide how to treat this message. This database is
% a struct array with fields:
% .identifier  - message id
% .level       - message severity level. One of
%                'info'    - print message
%                'warning' - print message, raise a warning
%                'error'   - print message, throw an error
% .destination - output destination. One of
%                'none'    - silently ignore this message
%                'stdout'  - standard output
%                'stderr'  - standard error output
%                'syslog'  - (UNIX) syslog
%                Warnings and errors will always be logged to the command
%                window and to syslog, if destination == 'syslog'. All
%                other messages will only be logged to the specified location.
% .verbose
% .backtrace   - control verbosity and backtrace, one of 'on' or 'off'
%
% function [oldsts msgids] = cfg_message('on'|'off', 'verbose'|'backtrace', msgidregexp)
% Set verbosity and backtrace display for all messages where msgid
% matches msgidregexp. To match a message id exactly, use the regexp
% '^msgid$'.
%

    
function varargout = cfg_message(varargin)

% function cfg_message(msgid, msgfmt, varargin)
% Display a message. The message identifier msgid will be looked up in a
% message database to decide how to treat this message. This database is
% a struct array with fields:
% .identifier  - message id
% .level       - message severity level. One of
%                'info'    - print message
%                'warning' - print message, raise a warning
%                'error'   - print message, throw an error
% .destination - output destination. One of
%                'none'    - silently ignore this message
%                'stdout'  - standard output
%                'stderr'  - standard error output
%                'syslog'  - (UNIX) syslog
%                Warnings and errors will always be logged to the command
%                window and to syslog, if destination == 'syslog'. All
%                other messages will only be logged to the specified location.
% .verbose
% .backtrace   - control verbosity and backtrace, one of 'on' or 'off'
%
% function [oldsts msgids] = cfg_message('on'|'off', 'verbose'|'backtrace', msgidregexp)
% Set verbosity and backtrace display for all messages where msgid
% matches msgidregexp. To match a message id exactly, use the regexp
% '^msgid$'.
%
% function [olddest msgids] = cfg_message('none'|'stdout'|'stderr'|'syslog', 'destination', msgidregexp)
% Set destination for all messages matching msgidregexp.
%
% function [oldlvl msgids] = cfg_message('info'|'warning'|'error', 'level', msgidregexp)
% Set severity level for all messages matching msgidregexp.
%
% For all matching message ids and message templates, the old value and
% the id are returned as cell strings. These can be used to restore
% previous settings one-by-one.
%
% This code is part of a batch job configuration system for MATLAB. See 
%      help matlabbatch
% for a general overview.
%_______________________________________________________________________
% Copyright (C) 2007 Freiburg Brain Imaging

% Volkmar Glauche
% $Id: cfg_message.m 380 2016-11-08 07:47:23Z tmoser $

rev = '$Rev: 380 $'; %#ok

if nargin < 1 || isempty(varargin{1})
    return;
end