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+# `0xF0` - TWisp
+This extension adds support for creating and forwarding PTY terminals through Wisp. The terminals act as streams with flow control, i.e. TCP streams.
+
+Streams created with the stream type `0x03` will ignore the requested port and treat the requested hostname as a command to run in a new PTY, so creating a stream with the destination hostname `/bin/bash` will run `/bin/bash` in a new PTY and forward input/output through the Wisp stream.
+
+## Server Message
+Empty
+
+## Client Message
+Empty
+
+## Additional Packets
+### `0xF0` - TWisp Resize
+| Field Name | Field Type | Notes                                            |
+|------------|------------|--------------------------------------------------|
+| Rows       | `uint16_t` | The number of rows to resize the terminal to.    |
+| Columns    | `uint16_t` | The number of columns to resize the terminal to. |
+
+This packet will resize the PTY for the stream ID it is sent with.