Supported environmental variables
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 PCILIB_PLUGIN_DIR 		- override path to directory with plugins
 
 PCILIB_DEBUG_DMA 		- Enable DMA debugging
 PCILIB_DEBUG_MISSING_EVENTS	- Enable debugging of missing events (frames for instance)
 IPECAMERA_DEBUG_BROKEN_FRAMES	- Store broken frames in the specified directory (variable may specify directory)
 IPECAMERA_DEBUG_RAW_PACKETS	- Store all raw packets read from DMA grouped in frames (variable may specify directory)
 IPECAMERA_DEBUG_RAW_FRAMES	- Store all raw frames (variable may specify directory)