如果未在星号中指定hangup(),则如何终止通道?

考虑asterisk/extensions.conf中的以下示例:

exten => 1,1,AGI(my)
exten => 2,1,Answer()
same => n,Playback(tt-weasels)
same => n,Hangup()

有必要在agi()之后指定hangup()吗?

如果改为使用extensions.conf,情况会如何变化?(与之前的不同之处在于 Answer() 使用)

exten => 1,1,Answer()
same => n,AGI(my)
exten => 2,1,Answer()
same => n,Playback(tt-weasels)
same => n,Hangup()

为了完整起见,这里是agi脚本:

#!/bin/sh
read; while [ "$REPLY" ]; do read; done
some-command
echo SET VARIABLE AGISTATUS SUCCESS; read