Parsing sed解析不带'；t exist似乎行为不一致

我有一个包含以下行的文件：

bash$ cat blah.txt
<smsDeliveryStatus value="Provider Malfunction"/>
<smsDeliveryStatus value="Provider Malfunction" id="23434"/>
<smsDeliveryStatus value="Delivery Failure"/>
<smsDeliveryStatus value="Delivery Successful" id="2"/>
bash$

这将从上述文件中产生以下结果：

value: Provider Malfunction
<smsDeliveryStatus value="Provider Malfunction"/>
value: Provider Malfunction
id: 23434
value: Delivery Failure
id: Unknown
value: Delivery Successful
id: 2

值：提供程序故障
值：提供程序故障
身份证号码：23434
价值：交付失败
身份证：未知
价值：交付成功
身份证号码：2

奇怪的是，缺少id的第一行被完整打印出来，缺少id的第二行按预期将id设置为未知。有人能解释为什么会发生这种情况吗？第一次/id/之间有什么区别！是读第二遍吗

---

A

我在文件中添加了多行，如下所示：

bash$ cat blah.txt
<smsDeliveryStatus value="Provider Malfunction"/>
<smsDeliveryStatus value="Provider Malfunction" id="23434"/>
<smsDeliveryStatus value="Delivery Failure"/>
<smsDeliveryStatus value="Delivery Successful" id="2"/>
<smsDeliveryStatus value="Provider Malfunction"/>
<smsDeliveryStatus value="Delivery Failure"/>
<smsDeliveryStatus value="Delivery Successful" id="2"/>
<smsDeliveryStatus value="Provider Malfunction" id="23434"/>
<smsDeliveryStatus value="Delivery Failure"/>
<smsDeliveryStatus value="Provider Malfunction"/>
bash$

所以最后我自己解决了。不过我希望这能帮助其他人

---

A/P>，我希望在处理XML类语言时可以考虑其他选项，而不是在它们上抛出正则表达式。我使用pythonxml.sax解析我的xml，但我还想再次检查sed和awk，以了解我个人的学习经验

bash$ cat blah.txt
<smsDeliveryStatus value="Provider Malfunction"/>
<smsDeliveryStatus value="Provider Malfunction" id="23434"/>
<smsDeliveryStatus value="Delivery Failure"/>
<smsDeliveryStatus value="Delivery Successful" id="2"/>
<smsDeliveryStatus value="Provider Malfunction"/>
<smsDeliveryStatus value="Delivery Failure"/>
<smsDeliveryStatus value="Delivery Successful" id="2"/>
<smsDeliveryStatus value="Provider Malfunction" id="23434"/>
<smsDeliveryStatus value="Delivery Failure"/>
<smsDeliveryStatus value="Provider Malfunction"/>
bash$

bash$ cat blah.txt |  sed -nr "/smsDeliveryStatus /{h; /value/ {s/.*value=\"([^\"]*)?\".*/value: \1/}; /value/! {s/.*/value: Unknown/}; p; x; /id/ {s/.*id=\"([^\"]*)\".*/id: \1/g}; /id/! {s/.*/id: Unknown/g}; p}"
value: Provider Malfunction
<smsDeliveryStatus value="Provider Malfunction"/>
value: Provider Malfunction
id: 23434
value: Delivery Failure
id: Unknown
value: Delivery Successful
id: 2
value: Provider Malfunction
<smsDeliveryStatus value="Provider Malfunction"/>
value: Delivery Failure
id: Unknown
value: Delivery Successful
id: 2
value: Provider Malfunction
id: 23434
value: Delivery Failure
id: Unknown
value: Provider Malfunction
<smsDeliveryStatus value="Provider Malfunction"/>
bash$ 

bash$ cat blah.txt |  sed -nr "/smsDeliveryStatus /{h; /value/ {s/.*value=\"([^\"]*)?\".*/value: \1/}; /value/! {s/.*/value: Unknown/}; p; x; /\bid\b/ {s/.*id=\"([^\"]*)\".*/id: \1/g}; /\bid\b/! {s/.*/id: Unknown/g}; p}"
value: Provider Malfunction
id: Unknown
value: Provider Malfunction
id: 23434
value: Delivery Failure
id: Unknown
value: Delivery Successful
id: 2
value: Provider Malfunction
id: Unknown
value: Delivery Failure
id: Unknown
value: Delivery Successful
id: 2
value: Provider Malfunction
id: 23434
value: Delivery Failure
id: Unknown
value: Provider Malfunction
id: Unknown
bash$ cat blah.txt