FW webcam USB light

cam-light-action.sh

#!/bin/zsh
# Use an USB light to let FW webcam see

PATH=$PATH:/usr/local/bin
UHCOPTS=$(uhubctl | awk '{ text=text"\n"$0; if ($0~/hub/) text=$0; if (text~/power$/) { print text; text="" } }' \
| awk -F',| |:' -v ORS=" " '{ print $5 }' | awk '{ print "-p "$2" -l "$1 }')

if [ -n "$UHCOPTS" ]; then
	uhubctl -a 0 ${=UHCOPTS}
	DEVNAME="iSight"; DEVGUID=$(system_profiler SPCameraDataType | awk -v dev="$DEVNAME:" -F':|x|-' '{ if ($0~dev) n=NR; if (NR==n+3 && NR!=3) print $3 }')
	IOFWUCC=$(ioreg -r -n IOFireWireDevice@$DEVGUID | awk -F'"' '/IOUserClientClass/ { print $4 }')
	RNUMBER=$(ioreg -r -n IOFireWireDevice@$DEVGUID | awk -F' |>' -v ucc=" $IOFWUCC  " '{ if ($0~ucc) { print $17; exit } }')
	while [ -n "$RNUMBER" ]; do
		OLDRNUM=$RNUMBER
		RNUMBER=$(ioreg -r -n IOFireWireDevice@$DEVGUID | awk -F' |>' -v ucc=" $IOFWUCC  " '{ if ($0~ucc) { print $17; exit } }')
		if [ $OLDRNUM -eq 5 -a $RNUMBER -eq 6 ]; then
			uhubctl -a 1 ${=UHCOPTS}
		fi
		if [ $OLDRNUM -eq 6 -a $RNUMBER -eq 5 ]; then
			uhubctl -a 0 ${=UHCOPTS}
		fi
		sleep 1
	done
fi

install.sh

#!/bin/sh
HL="$HOME/Library"; HLASCLA="$HL/Application Support/Camera Lights Action"; HLLA="$HL/LaunchAgents"
chmod a+rx cla.sh; mkdir $HLASCLA; cp cla.sh $HLASCLA; cp it.dardo82.CameraLightsAction.plist $HLLA
launchctl load -w "$HLLA/it.dardo82.CameraLightsAction.plist"

it.dardo82.CameraLightsAction.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>Label</key>
    <string>it.dardo82.CameraLightsAction</string>
    <key>ProgramArguments</key>
    <array>
	    <string>/Library/Application Support/Camera Lights Action/cla.sh</string>
    </array>
    <key>RunAtLoad</key>
    <true/>
</dict>
</plist>

uninstall.sh

#!/bin/sh

HL="$HOME/Library"; HLASCLA="$HL/Application Support/Camera Lights Action"; HLLA="$HL/LaunchAgents"
launchctl unload "$HLLA/it.dardo82.CameraLightsAction.plist"

Ok, thanks for input. I will start coding it, and will commit when ready - may take a week or two.
You can help by pushing it into homebrew: https://github.com/Homebrew/homebrew-head-only/pull/172 - I cannot comment on that thread, unfortunately. Thanks!

I can't, too... Sorry. :-/
Anyway, the ports are on by default so we can note which port is that before turning it off and then remember it to turn it on.