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[@salesforce/b2c-tooling-sdk](../../../modules.md) / [operations/logs](../index.md) / extractPrefix

# Function: extractPrefix()

> **extractPrefix**(`filename`): `string`

Defined in: [packages/b2c-tooling-sdk/src/operations/logs/list.ts:56](https://github.com/SalesforceCommerceCloud/b2c-developer-tooling/blob/e7c16f1ae423da0aa47b3e10be88f9770b53619b/packages/b2c-tooling-sdk/src/operations/logs/list.ts#L56)

Extracts the log prefix from a filename.

## Parameters

### filename

`string`

Log file name (e.g., "error-blade1-20250125.log")

## Returns

`string`

The prefix (e.g., "error") or "unknown"

## Example

```ts
extractPrefix("error-blade1-20250125.log") // "error"
extractPrefix("customerror-blade1-20250125.log") // "customerror"
extractPrefix("custom-mylog-blade1-20250125.log") // "custom-mylog"
```