Address people using 生 (e.g. 唐生) Sometimes I hear people from Southern China address other people using 生, e.g. 唐生 for 张国荣's lover 唐鹤德. I looked it up in the dictionaries and searched online but didn't found any explanation on the usages. Here are my questions:


What does it mean? Is it short for/related to 先生 or 小生?
What gender/age/profession do you use it for? Is it exclusively used for young male? 
Is it regional? (Personally I have never heard of it in Northern China.)
Is it formal or colloquial?
In Cantonese, 先生 can be shortened to 生 when attached to a family name. It is used for adult male, all ages and is used orally, not written.