releasing 1 pending lock... at /usr/share/perl5/vendor_perl/LockFile/Simple.pm line 206.

[tanzhenchao]

1. Run environment
   Operating system: CentOS 7.3 x86_64
   Roundcube version: 1.4-beta
   Perl version: v5.16.3
   Database: MariaDB 5.5.56
   RCimapSync version: 1.1.2

2. Run the belown command,

cd /var/www/mail.cmdschool.org/plugins/imapsync/bin
./imapsync.pl

message see belown,

releasing 1 pending lock... at /usr/share/perl5/vendor_perl/LockFile/Simple.pm line 206.

3. Locate the wrong line, see detail belown，

sub core_warn   { CORE::warn(@_) }

4. Could you tell me how to solve this problem? Thanks！