# Environment Variable Bypass Wildcard

If you need to use a variable in computing contexts, especially on Windows systems, you may encounter a variable format like `%username%`.\
In Helmut3 and early versions of Helmut4, wildcards were defined using the format `%user.name%`. However, to ensure compatibility with various other systems, this convention has been changed to `{user.name}`.

In modern versions, the stream engine no longer resolves the `%` wildcards in the preview but still converts them.\
If you need to use this format in a "write file" output action or any other node like JavaScript, you can employ an escape wildcard to bypass automatic resolution.

These changes enhance readability and clarity while maintaining the original content's meaning.

### Syntax to bypass

*\[<]environment variable\[>]*

#### Example

<figure><img src="/files/Bb1SDn6DPPosR8c0M6AQ" alt="" width="375"><figcaption><p>Wildcards with {} and %% style</p></figcaption></figure>

<figure><img src="/files/Zt0Q1xMQ159MTqcNrqF6" alt="" width="375"><figcaption><p>Response and compare for resolving bypass</p></figcaption></figure>

{% hint style="info" %}
This wildcard is not an official wildcard and is not documented within Streamdesigner. Consider it as a secret Swiss army knife tool in case it is needed.
{% endhint %}


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```
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```

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