Moodle mtrace modification that makes PID appear in cron logs

mtrace-console-pid.patch

commit xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Author: David Mudrák <david@moodle.com>
Date:   Mon Jan 21 15:49:09 2019 +0100

    Include PID in mtrace console output, e.g. in cron logs

diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index 18e7a74cef..8d45d8d84c 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -8949,7 +8949,7 @@ function mtrace($string, $eol="\n", $sleep=0) {
         $fn($string, $eol);
         return;
     } else if (defined('STDOUT') && !PHPUNIT_TEST && !defined('BEHAT_TEST')) {
-        fwrite(STDOUT, $string.$eol);
+        fwrite(STDOUT, '[PID '.(string) getmypid().'] '.$string.$eol);
     } else {
         echo $string . $eol;
     }