[FFmpeg-user] Infinite loop on color bars

[Andrew Sinclair]

Does anyone know if it is possible to create an infinite loop off a test
source? This would be very useful for testing live streams

e.g.
ffmpeg -f lavfi -i smptebars -t 10000000000000  -c:v libx264 -an -f flv
rtmp://streamingserver/live/stream01

I am just make -t a large number but would like to know if there is a flag
to make this infinite.