Return to Answer

1. How to configure X to ignore the keyboard

Use lsusb to find the ID of your barcode scanner (in format 0123:4567). Create or modify an xorg.conf file (usually in /etc/X11/). Add a InputClass section with the ID you just found:

Section "InputClass"
    Identifier "barcode"
    MatchUSBID "0123:4567"
    Option "Ignore" "true"
EndSection

Restart X, verify in Xorg.log that your device is recognized by this section and ignored.

2. The conversion from keypresses to ASCII (or other) codes is pretty involved, to allow for different keyboard layouts, dead keys, customizations etc. Now that you disabled the X conversion layer, you can receive keypress and keyrelease events from the appropriate /dev/input/eventX device. The number can change; for your barcode reader, there will be a symlink in /dev/input/by-id/ which doesn't change. So use the symlink.

You can run evtest on this file to see what kind of events it generates. They mapping for your barcode reader will be simple, so a table lookup from keysym to ASCII code will do. You can process these events in your own program, see the evtest source, or e.g. here. You can also write a small C program which just reads this device and produces ASCII on stdout, and then integrate it into your application using a pipe etc.

"Mapping it as an ASCII stream device" is not possible, such devices don't exist in the Linux kernel.

3. Setting permissions

You need to write a custom udev rule to set permissions for your input device. SUBSYSTEM must match input, ACTION must match ADD, the environment ENV should contain information to match the device (use udevadm to find out details), and you can set OWNER, GROUP and MODE for the newly created /dev/input/eventX device. Here's a somewhat general howto , I couldn't find a more specific one. Google for better tutorials.

1. How to configure X to ignore the keyboard

Use lsusb to find the ID of your barcode scanner (in format 0123:4567). Create or modify an xorg.conf file (usually in /etc/X11/). Add a InputClass section with the ID you just found:

Section "InputClass"
    Identifier "barcode"
    MatchUSBID "0123:4567"
    Option "Ignore" "true"
EndSection

Restart X, verify in Xorg.log that your device is recognized by this section and ignored.

2. The conversion from keypresses to ASCII (or other) codes is pretty involved, to allow for different keyboard layouts, dead keys, customizations etc. Now that you disabled the X conversion layer, you can receive keypress and keyrelease events from the appropriate /dev/input/eventX device. The number can change; for your barcode reader, there will be a symlink in /dev/input/by-id/ which doesn't change. So use the symlink.

You can run evtest on this file to see what kind of events it generates. They mapping for your barcode reader will be simple, so a table lookup from keysym to ASCII code will do. You can process these events in your own program, see the evtest source, or e.g. here. You can also write a small C program which just reads this device and produces ASCII on stdout, and then integrate it into your application using a pipe etc.

"Mapping it as an ASCII stream device" is not possible, such devices don't exist in the Linux kernel.

3. Setting permissions

You need to write a custom udev rule to set permissions for your input device. SUBSYSTEM must match input, ACTION must match ADD, the environment ENV should contain information to match the device (use udevadm to find out details), and you can set OWNER, GROUP and MODE for the newly created /dev/input/eventX device. Here's a somewhat general howto , I couldn't find a more specific one. Google for better tutorials.

1. How to configure X to ignore the keyboard

Use lsusb to find the ID of your barcode scanner (in format 0123:4567). Create or modify an xorg.conf file (usually in /etc/X11/). Add a InputClass section with the ID you just found:

Section "InputClass"
    Identifier "barcode"
    MatchUSBID "0123:4567"
    Option "Ignore" "true"
EndSection

Restart X, verify in Xorg.log that your device is recognized by this section and ignored.

2. The conversion from keypresses to ASCII (or other) codes is pretty involved, to allow for different keyboard layouts, dead keys, customizations etc. Now that you disabled the X conversion layer, you can receive keypress and keyrelease events from the appropriate /dev/input/eventX device. The number can change; for your barcode reader, there will be a symlink in /dev/input/by-id/ which doesn't change. So use the symlink.

You can run evtest on this file to see what kind of events it generates. They mapping for your barcode reader will be simple, so a table lookup from keysym to ASCII code will do. You can process these events in your own program, see the evtest source, or e.g. here. You can also write a small C program which just reads this device and produces ASCII on stdout, and then integrate it into your application using a pipe etc.

"Mapping it as an ASCII stream device" is not possible, such devices don't exist in the Linux kernel.

3. Setting permissions

You need to write a custom udev rules to set permissions for your input device. SUBSYSTEM must match input, ACTION must match ADD, the environment ENV should contain information to match the device (use udevadm to find out details), and you can set OWNER, GROUP and MODE for the newly created /dev/input/eventX device. Here's a somewhat general howto , I couldn't find a more specific one. Google for better tutorials.

1. How to configure X to ignore the keyboard

Use lsusb to find the ID of your barcode scanner (in format 0123:4567). Create or modify an xorg.conf file (usually in /etc/X11/). Add a InputClass section with the ID you just found:

Section "InputClass"
    Identifier "barcode"
    MatchUSBID "0123:4567"
    Option "Ignore" "true"
EndSection

Restart X, verify in Xorg.log that your device is recognized by this section and ignored.

2. The conversion from keypresses to ASCII (or other) codes is pretty involved, to allow for different keyboard layouts, dead keys, customizations etc. Now that you disabled the X conversion layer, you can receive keypress and keyrelease events from the appropriate /dev/input/eventX device. The number can change; for your barcode reader, there will be a symlink in /dev/input/by-id/ which doesn't change. So use the symlink.

You can run evtest on this file to see what kind of events it generates. They mapping for your barcode reader will be simple, so a table lookup from keysym to ASCII code will do. You can process these events in your own program, see the evtest source, or e.g. here. You can also write a small C program which just reads this device and produces ASCII on stdout, and then integrate it into your application using a pipe etc.

"Mapping it as an ASCII stream device" is not possible, such devices don't exist in the Linux kernel.

3. Setting permissions

You need to write a custom udev rule to set permissions for your input device. SUBSYSTEM must match input, ACTION must match ADD, the environment ENV should contain information to match the device (use udevadm to find out details), and you can set OWNER, GROUP and MODE for the newly created /dev/input/eventX device. Here's a somewhat general howto , I couldn't find a more specific one. Google for better tutorials.

1. How to configure X to ignore the keyboard

Use lsusb to find the ID of your barcode scanner (in format 0123:4567). Create or modify an xorg.conf file (usually in /etc/X11/). Add a InputClass section with the ID you just found:

Section "InputClass"
    Identifier "barcode"
    MatchUSBID "0123:4567"
    Option "Ignore" "true"
EndSection

Restart X, verify in Xorg.log that your device is recognized by this section and ignored.

2. The conversion from keypresses to ASCII (or other) codes is pretty involved, to allow for different keyboard layouts, dead keys, customizations etc. Now that you disabled the X conversion layer, you can receive keypress and keyrelease events from the appropriate /dev/input/eventX device. The number can change; for your barcode reader, there will be a symlink in /dev/input/by-id/ which doesn't change. So use the symlink.

You can run evtest on this file to see what kind of events it generates. They mapping for your barcode reader will be simple, so a table lookup from keysym to ASCII code will do. You can process these events in your own program, see the evtest source, or e.g. here. You can also write a small C program which just reads this device and produces ASCII on stdout, and then integrate it into your application using a pipe etc.

"Mapping it as an ASCII stream device" is not possible, such devices don't exist in the Linux kernel.

1. How to configure X to ignore the keyboard

Use lsusb to find the ID of your barcode scanner (in format 0123:4567). Create or modify an xorg.conf file (usually in /etc/X11/). Add a InputClass section with the ID you just found:

Section "InputClass"
    Identifier "barcode"
    MatchUSBID "0123:4567"
    Option "Ignore" "true"
EndSection

Restart X, verify in Xorg.log that your device is recognized by this section and ignored.

2. The conversion from keypresses to ASCII (or other) codes is pretty involved, to allow for different keyboard layouts, dead keys, customizations etc. Now that you disabled the X conversion layer, you can receive keypress and keyrelease events from the appropriate /dev/input/eventX device. The number can change; for your barcode reader, there will be a symlink in /dev/input/by-id/ which doesn't change. So use the symlink.

You can run evtest on this file to see what kind of events it generates. They mapping for your barcode reader will be simple, so a table lookup from keysym to ASCII code will do. You can process these events in your own program, see the evtest source, or e.g. here. You can also write a small C program which just reads this device and produces ASCII on stdout, and then integrate it into your application using a pipe etc.

"Mapping it as an ASCII stream device" is not possible, such devices don't exist in the Linux kernel.

3. Setting permissions

You need to write a custom udev rules to set permissions for your input device. SUBSYSTEM must match input, ACTION must match ADD, the environment ENV should contain information to match the device (use udevadm to find out details), and you can set OWNER, GROUP and MODE for the newly created /dev/input/eventX device. Here's a somewhat general howto , I couldn't find a more specific one. Google for better tutorials.