Vicon Evoke banner

Evoke supports the following command-line options that control functionality.



Show a dialog listing the available command-line options.

--log arg

Set default log level to one of Off, Always, Error, Warn, Info, Default, or Debug. The default value is Default.

Setting to Off turns off all logging. Other options enable logging at that level of priority or higher.

For example, at Default level, messages at levels Always, Error, Warn, Info, and Default are logged to file.

Unless the Advanced Options panel is shown from the Log context menu, the Log view in the application always hides messages at levels Default and Debug.


Force Qt to use OpenGL ES. This may help to work around graphics driver issues.

--crash-handler arg

Set the crash handler [omg, quiet, system]. The default value is omg.

omg - Use the OMG Error Reporting tool to send a report to Vicon support (requires internet access)
quiet - Suppress any error dialogs on crash, and save a report to C:\Users\Public\Documents\Vicon\ErrorReporting
system - Default Windows handling of crashes

--terminal-port arg

Set the port to use for the Vicon Core API terminal server. The default option is 52800.

--log-dir arg

Set the directory to use for log files. The default value is C:\Users\Public\Documents\Vicon\Evoke1.#\Log

--max-log-files arg

Set the maximum number of log files to keep. The default value is 20.


Set the host IP address to use for the Vicon system. The default value is


Suppress prompt to update if not running the latest application version. This may be useful when running as a headless service.


Suppress the application splash screen.

For example, to save a maximum of 100 log files to C:\EvokeLogs, run Evoke with the command:

Evoke.exe --log-dir=C:\EvokeLogs --max-log-files=100

Evoke Headless

Evoke Headless shares the same settings and preferences as Evoke and has additional options for handling error reporting. In the event of an application crash, Evoke Headless is configured by default to send a report to Vicon, so that the problem can be investigated and fixed. The following command line options control this behavior:



Specify an email address for correspondence in error reports sent to Vicon Support.


Turn off automatically sending error reports to Vicon Support. Crash reports are still saved to

These reports may be sent to Vicon at a later date with the OMG Error Reporting tool:

C:\Program Files\Vicon\Evoke1.#\OMGErrorReporting.exe --upload-all