# Enable or Disable Error Logging

You can enable or disable error logging using either the API or environment variables. By default, a file called `kvoop.log` is created in the system temporary directory; however, you can change the path and file name of this file (see Change the Path and File Name of the Log File).

## Use the API

To enable or disable logging in the API, instantiate the Filter object using the constructor `Filter(String outputCharSet, UInt32 filterFlags)`, and set the `FilterConstant.FilterFlagConstant` argument to either `FILTERFLAG_OOPLOGON` or `FILTERFLAG_OOPLOGOFF`. For example:

    objFilter = new Filter(outputCharSet, FilterConstant.FilterFlagConstant.FILTERFLAG_OOPLOGON);

## Use Environment Variables

To enable logging, add the environment variable `KVOOPLOGON`, and set the variable value to 1. To disable logging, do not set the environment variable `KVOOPLOGON`.

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