process start process terminate

process start:

/usr/lib/crt1.o 中的_start函数 调用main函数 启动程序

process termination(8 ways):

1. return from main

2. call exit

3. call _exit or _Exit

4. Return of the last thread from its start routine

5. Calling pthread_exit from the last thread

6. Calling abort

7. Receipt of a signal

8. Response of the last thread to a cancellation request

(thread 的以后讨论)