Also heed the security warning in the FAQ item I linked above, and circumvent the security issue with a custom appender like (the untested): 

package Log::Log4perl::Appender::HJOfilnamed;
use parent qw[ Log::Log4perl::Appender::File ];
use POSIX();
sub new {
    my $class = shift;
    my %opts  = @_;
    my $tim   = POSIX::strftime('%Y-%m-%dT%H-%M-%SZ', gmtime);
    my $fname = join '.', grep defined, $opts{name}, $opts{appender}, 
+$tim, 'log';
    $fname =~ s{::}{.}g;
    $fname =~ s{[^0-9a-zA-Z\-\+\.}{}g;
    $fname = $1 if $fname =~ /^(.*)$/
    return $class->new( @_, filename => $fname );
}

[download]
So  log4perl.appender.myFILE = Log::Log4perl::Appender::HJOfilnamed gets you a  MyApp.myFILE.2012-10-29T02-40-04Z.log

You'd probably want to set other defaults to your liking :)( layout, mode, ... )

In reply to Re^2: Can I from within a module access variables from the calling program? by Anonymous Monk
in thread Can I from within a module access variables from the calling program? by HJO

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