new code

use strict;
use warnings;
use MIME::Lite;
use FileHandle;
use File::Copy;
use Logfile::Rotate;
use Fcntl qw(:flock);


flock($RLOG, LOCK_SH|LOCK_NB) || warn "no NB lock $!";
flock($MLOG, LOCK_SH|LOCK_NB) || warn "no NB lock $!";
[download]

well similar error NOW: error: can not open: (1)

As you should. You're locking the file for reading, which prevents Logfile::Rotate from getting an exclusive lock on the file. Why are you locking the file?

I did not intentionally lock the file. Rather I only add the 'flock' calls after I got this error after adding add'l code to my logfile rotate sub.

I also told logfile rotate Flock => no, but that does not rid of my error.

Here is my logfile rotate code:

sub _logroll($;$) {

    my $gzip;
    eval qq(use Compress::Zlib);
        if ($@) {
            $gzip = q(/usr/bin/gzip);
        }
        else {
            $gzip = q(lib);
        }

    if ( scalar @_ == 1 ) {
        my $roll1 = @_;
        my $rollog1 = new Logfile::Rotate(
           File     => $roll1,
           Count    => 15,
           Dir      => $dir,
           Gzip     => $gzip,
           Flock    => 'no',
           Persist  => 'yes'
        );
        $rollog1->rotate();
    }
    elsif ( scalar @_ == 2 ) {
        my ($roll1, $roll2) = @_;
        my $rollog2 = new Logfile::Rotate(
           File     => $roll1,
           Count    => 15,
           Dir      => $dir,
           Gzip     => $gzip,
           Flock    => 'no',
           Persist  => 'yes'
        );

        my $rollog2a = new Logfile::Rotate(
           File      => $roll2,
           Count     => 15,
           Dir       => $dir,
           Gzip      => $gzip,
           Flock     => 'no',
           Persist   => 'yes'
        );
        
        $_->rotate() for ($rollog2, $rollog2a);
    }
}
[download]

later in my code I am '>>' to this same file from a system command called mksysb, so that looks like:

 system ("mksysb /dev/$rmt -A -e -m -p -X >> $mksysblog 2>&1");