# cu (character update) processing code

The cu processing code allows data in
a defined attribute with an output-conversion (attribute 7) or correlative
(attribute 8) to be changed character by character with the Update
processor. The cu processing code is placed in
the input-conversion (attribute 14). If cu is not
specified, existing data is erased and nulled when editing is started.

| System Processors | Update |
| --- | --- |
| Code Type | Attribute Defining |
| Dictionary Attributes | Input Conversion |

## Syntax

```
cu
```

## Description

The cu processing
code is required only when there is another conversion present in
the attribute-defining item. For example, having a cu processing code within an attribute that contains a date and a corresponding d output-conversion code in its attribute-defining item
allows changing part of the date field, rather than having to re-enter
the entire date.

Note: If a cu processing code
is included without any additional input-conversions, the string is
written to the file as it displays on the screen. If this is not desired,
an input-conversion must be added to reverse the affect of the output-conversion/correlative.

## See also

- [Processing codes (Update processor)](https://d3codex.com/updateprocessor/processing-codes-update-processor/)
- [output-conversion](https://d3codex.com/attributedefiningitem/output-conversion/)
- [Processing codes overview](https://d3codex.com/processingcodes/processing-codes-overview/)
- [Processing codes (Update processor)](https://d3codex.com/updateprocessor/processing-codes-update-processor/)

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Source: https://d3codex.com/processingcodes/cu-character-update-processing-code/ - part of the D3Codex reference.