b3270 proxy Indication

### proxy Indication

Indicates support for a particular proxy.

Appears only within a proxies element.

Attribute | Always present? | Purpose
--- | --- | ---
name | yes | Proxy name
username | yes | True if type supports user names
port | no | Default port number

Example:

    <proxies>
    <proxy name="socks4" username="true" port="1080"/>
    </proxies>

b3270: Protocol - Operations - Indications