UNABLE(1) UNABLE(1) (NAME) unable - v4l2 loopback (SYNOPSIS) v4l2loopback-ctl [OPTIONS] v4l2loopback-ctl add [OPTIONS] [ []] v4l2loopback-ctl delete v4l2loopback-ctl list [OPTIONS] v4l2loopback-ctl query [OPTIONS] v4l2loopback-ctl set-fps v4l2loopback-ctl get-fps v4l2loopback-ctl set-caps v4l2loopback-ctl get-caps v4l2loopback-ctl set-timeout-image [OPTIONS] (DESCRIPTION) v4l2 loopback. ( 'add' 'delete') . . (OPTIONS) -h, -?, --help: -v, --version: (VERBS AND THEIR ARGUMENTS) v4l2loopback-ctl add [OPTIONS] [ []]: / loopback -b , --buffers -h , --max-height -n , --name -o , --max-openers -v, --verbose ( ) -w , --max-width -x , --exclusive-caps OUTPUT/CAPTURE --min-width --min-height -?, --help ( ). ( '/dev/video1') ('1') . ( ). v4l2loopback-ctl delete : loopback ( ). ( '/dev/video1') ('1') . v4l2loopback-ctl list [OPTIONS]: loopback -e, --escape (escape) () -h, --help v4l2loopback-ctl query [OPTIONS] : loopback -e, --escape () -h, --help ( ). ( '/dev/video1') ('1') . v4l2loopback-ctl set-fps : loopback ( '/dev/video1') ('1') . ('30') ('50/2'). v4l2loopback-ctl get-fps : loopback v4l2loopback-ctl set-caps : // loopback ( '/dev/video1') ('1') . ':x@' ( 'UYVY:1024x768@60/1') 'any' v4l2loopback-ctl get-caps : // loopback v4l2loopback-ctl set-timeout-image [OPTIONS] : (fallback) . -h, --help -t , --timeout ( ) -v, --verbose ( ) ( '/dev/video1') ('1') . (BUGS) : https://github.com/umlaeute/v4l2loopback/issues : https://git.iem.at/zmoelnig/v4l2loopback/-/issues utils/v4l2loopback-ctl v0.15.4 unable to open control device '/dev/v4l2loopback': No such file or directory August 2026 UNABLE(1)