How unique id in sugar crm modules such as in Emails module are generated?

Need to know that how "create_guid" function work and how it generate IDs for different modules e.g. Emails module?

You may just call it like

$next_meeting->id = create_guid();

for example in logic hook. The function itself placed in /include/utils.php file .

Of course, you have to save newly generated bean with

$next_meeting->save();