fix issue when not able to connect with receiver (added udev rule)

Author: marcelhoffs

README.md

@@ -31,8 +31,15 @@ This is a Visual Basic script that is just a wrapper around switch_to_2.bat. If
 From the **Linux** folder, copy both files (switch_to_1.sh & hidapitester) to: **/usr/bin**
 ```
 cd linux
-sudo cp * /usr/bin
+sudo cp hidapitester /usr/bin
+sudo cp switch_to_1.sh /usr/bin
+sudo cp 42-logitech-unify.rules /usr/lib/udev/rules.d
+chmod +x /usr/bin/hidapitester
+chmod +x /usr/bin/switch_to_1.sh
 ```
+If you have Solaar installed copying the 42-logitech-unify.rules file is not needed. If you don't have Solaar installed you will probably notice that hidapitester does not work without root permissions (e.g. via sudo). This is because non-root users do not have raw access to the hid devices by default.
+So the 42-logitech-unify.rules file is a udev rule that allows raw access to the Logitech Unify receiver for non-root users. You might have to unplug your receiver and plug it in again.
+
 Now in your desktop environment of choice, define a custom shortcut. In my case I have used the "Menu" key on my keyboard and assigned it to execute **/usr/bin/switch_to_1.sh**.
 
 ## 3.1 - switch_to_1.sh

linux/42-logitech-unify.rules

@@ -0,0 +1,28 @@
+# This rule to allow users (non-root) to have raw access to Logitech receiver
+
+ACTION != "add", GOTO="endrule"
+SUBSYSTEM != "hidraw", GOTO="endrule"
+
+# USB-connected Logitech receivers and devices
+ATTRS{idVendor}=="046d", GOTO="applyrule"
+
+# Lenovo nano receiver
+ATTRS{idVendor}=="17ef", ATTRS{idProduct}=="6042", GOTO="applyrule"
+
+# Bluetooth-connected Logitech devices
+KERNELS == "0005:046D:*", GOTO="applyrule"
+
+GOTO="endrule"
+
+LABEL="applyrule"
+
+# Allow any seated user to access the receiver.
+# uaccess: modern ACL-enabled udev
+# udev-acl: for Ubuntu 12.10 and older
+TAG+="uaccess", TAG+="udev-acl"
+
+# Grant members of the "plugdev" group access to receiver (useful for SSH users)
+#MODE="0660", GROUP="plugdev"
+
+LABEL="endrule"
+# vim: ft=udevrules