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The sysinit sub application is used to install Xilinx Gstreamer and Video packages to facilitate the use of the advanced multi-media features of the Zynq UltraScale+ MPSoC device. This sub app should be executed after first boot of the system.
With xlnx-config installed in the system, you can view the sysinit script at /snap/xlnx-config/current/bin/sysinit.sh
Installation
To install xlnx-config, you must include the --classic option since this is a classic confined snap:
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