Your syslogd is perhaps using 'udp' by default, try the setlogsock() function (see docs):

    use Sys::Syslog qw/:DEFAULT setlogsock/;

    setlogsock('unix');
    openlog($0, 'pid', 'user');
    syslog('notice', 'blah blah: %d', time());
    closelog();
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There is also the Unix::Syslog module with an interface more like the unix syslog call:

    use Unix::Syslog qw/:subs :macros/;

    openlog($0, LOG_PID, LOG_USER);
    syslog(LOG_NOTICE, 'blah blah: %d', time());
    closelog();
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