Android Zygote

1. Linux kernel start the 1st process - init
2. init fork a child process - ServiceManager 
3. init fork a child process - Zygote
4. Zygote 
1. Fork an child process for SystemServer (register to ServiceManager)
2. Main process is waiting to fork child processes of user applications from ActivityManagerService via socket

• Linux - fork() function
• return child pid in parent process
• return 0 in child process