# xmlstarlet

```
<root>
    <elem>
        <node n="132">
            <type>face</type>
        </node>
        <desc>hello</desc>
    </elem>
    <node n = '456'>
        <type>face</type>
    </node>
    <desc>bye</desc> 
    <node>
        <type>iris</type>
    </node>   
</root>
```

#### Extract  element value constraint by sibling condition:

`x=$(xml sel -t -v "//elem/node[type='face']/../desc" root.xml)`

The above extracts the `desc` element value if `node` and `desc` are siblings and `node` has a `type` child node with value `face`.  The parent of the two siblings is `elem`.&#x20;

#### Extract element value constraint by element attribute value

`xml sel -t -v "//node[@n='123']/type" root.xml`

#### `Extract element value constraint by element attribute presence`

`xml sel -t -v "//node[not(@n)]/type" root.xml`

#### Extract element value constraint by parent element

#### Extract element value constraint by parent element attribute

#### Extract element value constraint by child element

#### Extract element constraint by its value

#### Count elements

#### Count elements having any of the above constraint


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