If I use export variable method, the next bash shell can ignore eof(press ^D won't exit).
But, I want the child bash could exit by press ^D.
Is there any command line option of bash could do this job?

```
export ignoreeof=1
exec bash  # assume this bash's pid = 1234
bash$  ^D  
bash$  Use "exit" to leave the shell.
bash$  bash  # assume this bash's pid = 2234
bash$  ^D  <--  I wish this could exit bash(pid=2234)

```