Set the AVITRACE environment variable to the required trace level. See your operating system documentation for further details.

Note:
The TRACE setting in the Initialisation File takes precedence over the AVITRACE environment variable. The AVITRACE environment variable will only be used if the Initialisation File cannot be read or the TRACE setting in the initialisation file is missing, invalid or set to zero. This means that the AVITRACE environment variable has no effect if there is a valid non-zero TRACE setting in the initialisation file.