我有一个包含以下行的文件:

  <parameter name="PortMappingEnabled" access="readWrite" type="xsd:boolean"></parameter>
  <parameter name="PortMappingLeaseDuration" access="readWrite" activeNotify="canDeny" type="xsd:unsignedInt"></parameter>
  <parameter name="RemoteHost" access="readWrite"></parameter>
  <parameter name="ExternalPort" access="readWrite" type="xsd:unsignedInt"></parameter>
  <parameter name="ExternalPortEndRange" access="readWrite" type="xsd:unsignedInt"></parameter>
  <parameter name="InternalPort" access="readWrite" type="xsd:unsignedInt"></parameter>
  <parameter name="PortMappingProtocol" access="readWrite"></parameter>
  <parameter name="InternalClient" access="readWrite"></parameter>
  <parameter name="PortMappingDescription" access="readWrite"></parameter>

我想对该文件执行命令以仅提取以下输出中显示的参数名称:

$sedcommand file.txt
PortMappingEnabled
PortMappingLeaseDuration
RemoteHost
ExternalPort
ExternalPortEndRange
InternalPort
PortMappingProtocol
InternalClient
PortMappingDescription

这个命令是什么？

最佳答案

grep 为提取东西而生:

grep -Po 'name="\K[^"]*'

使用您的数据进行测试:

kent$  echo '<parameter name="PortMappingEnabled" access="readWrite" type="xsd:boolean"></parameter>
  <parameter name="PortMappingLeaseDuration" access="readWrite" activeNotify="canDeny" type="xsd:unsignedInt"></parameter>
  <parameter name="RemoteHost" access="readWrite"></parameter>
  <parameter name="ExternalPort" access="readWrite" type="xsd:unsignedInt"></parameter>
  <parameter name="ExternalPortEndRange" access="readWrite" type="xsd:unsignedInt"></parameter>
  <parameter name="InternalPort" access="readWrite" type="xsd:unsignedInt"></parameter>
  <parameter name="PortMappingProtocol" access="readWrite"></parameter>
  <parameter name="InternalClient" access="readWrite"></parameter>
  <parameter name="PortMappingDescription" access="readWrite"></parameter>
'|grep -Po 'name="\K[^"]*'
PortMappingEnabled
PortMappingLeaseDuration
RemoteHost
ExternalPort
ExternalPortEndRange
InternalPort
PortMappingProtocol
InternalClient
PortMappingDescription

https://stackoverflow.com/questions/16675179/