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Top xorg frequently asked interview questions

On Ubuntu 9.10, where is the xorg.conf file in Karmic Koala?

I am trying to change this xorg.conf file that I used to modify under Ubuntu 9.04, so it can have the higher resolutions of my monitor. Under 9.04, the monitor was unknown, and I had to key in all resolutions in the file, and although it is found under 9.10, 9.10 does not have the highest resolution that my monitor can sustain.

How can I change such a setting? Is xorg.conf moved, or replaced?


Source: (StackOverflow)

Where is xorg.conf in Ubuntu 10.04?

I'm in the middle of trying to setup dual monitors on ubuntu and would like to backup my xorg.conf...

The documentation I've been thus far say to do the following:

sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf_backup

But I don't see the xorg.conf file anywhere... Am I missing something? Where is this located?


Source: (StackOverflow)

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Get display resolution from the command line for Linux Desktop

I'm looking for a method of reporting display resolution. I want to set up scripts to launch rdesktop, and I want to launch it on several machines with different resolutions, so I want a way to dynamically determine it.


Source: (StackOverflow)

Detecting currently active window

The linux commandline tool wmctrl allows you to list all windows, or all desktops, among other things. In the desktop-listing mode, the current desktop is marked with an asterisk.

I need a tool that can figure out the currently active window's title. Unfortunately, wmctrl doesn't have a helper that does this - despite it knowing which window is currently active (see :ACTIVE: marker).

Is there another commandline tool that can give me the window id and/or window title of the current window?


Source: (StackOverflow)

Alt+click-drag window resizing on a Mac? (Similar to X-Windows)

Is there a way I can get this behavior on Mac OS?

  1. alt + right-click-drag will resize the window, relative to where you've clicked within the window and the window's center

  2. alt + left-click-drag will move the window, regardless of where you've clicked within the window.

There's a Windows port of this behavior as well: http://www.codeproject.com/KB/DLL/wm.aspx


Source: (StackOverflow)

How do I restart a frozen screen in Ubuntu without losing any open windows?

I had a device running Ubuntu 12.04 LTS have its screen freeze. Generally I have simply jumped onto an available tty, i.e. Ctrl-Alt-F1 and executed the command /etc/init.d/lightdm restart or service lightdm restart. This however kills everything I have open. How do I avoid this?


Source: (StackOverflow)

How do I find out my screen resolution from a shell script?

How do I find out my screen resolution from a shell script?


Source: (StackOverflow)

.Xresources or .Xdefaults?

These two files seem to have the same function. What is the difference between the two if any?


Source: (StackOverflow)

How do I fix a "cannot open display" error when opening an X program after ssh'ing with X11 forwarding enabled?

After launching the X11 app (XQuartz 2.3.6, xorg-server 1.4.2-apple56) on my Mac (OS X 10.6.8), opening an terminal in X11 and running xhost +, I then ssh -Y to my Ubuntu 10.04 VM (running on VMware Fusion). When I run gedit .bashrc (for example), I get:

(gedit:9510): Gtk-WARNING **: cannot open display: 

set | grep DISPLAY returns nothing.

But if I ssh -Y into my Ubuntu 11.04 machine, gedit .bashrc works. echo $DISPLAY returns "localhost:10.0".

I tried export DISPLAY=localhost:10.0 while sshed into my VM and then running gedit .bashrc, but I get:

(gedit:9625): Gtk-WARNING **: cannot open display: localhost:10.0

What could be different in the configuration of the two difference Ubuntu machines that would explain why one works and the other doesn't?

Update: As suggested by Zoredache in the comment below, I ran sudo apt-get install xbase-clients, but I continue to have the same problem.


Source: (StackOverflow)

how to set the mouse speed very low on ubuntu

I set the mouse acceleration and sensitivity levels to minimum in System->Preferences->Mouse but with the new mouse I have, even those settings are too fast. Is there a way to further reduce the speed? The resolution of the mouse seems to be much higher than needed. Is there a way to reduce that?. The mouse is an Okano A1020 Laser Mouse. lsusb -v says the following:

    Bus 006 Device 002: ID 12cf:0047  
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               1.10
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0         8
  idVendor           0x12cf 
  idProduct          0x0047 
  bcdDevice           51.04
  iManufacturer           1 MouseCenter
  iProduct                2 LASER Mouse
  iSerial                 0 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           34
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xa0
      (Bus Powered)
      Remote Wakeup
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         3 Human Interface Device
      bInterfaceSubClass      1 Boot Interface Subclass
      bInterfaceProtocol      2 Mouse
      iInterface              0 
        HID Device Descriptor:
          bLength                 9
          bDescriptorType        33
          bcdHID               1.11
          bCountryCode            0 Not supported
          bNumDescriptors         1
          bDescriptorType        34 Report
          wDescriptorLength      46
         Report Descriptors: 
           ** UNAVAILABLE **
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0008  1x 8 bytes
        bInterval              10
Device Status:     0x0000
  (Bus Powered)

EDIT: In the meantime, I tried xset m 0 0, which didn't improve anything either, the mouse stayed at the same speed.

another edit: Thanks for asking, I didn't notice this earlier. The acceleration setting does have an effect, but the sensitivity setting does not. Also, I double checked the company name and model, and it is correct as stated.


Source: (StackOverflow)

Disabling mouse acceleration in X.Org (Linux)

This is the Linux version of my Disabling mouse acceleration in Mac OS X question. Hopefully I'll get an answer this time.

I am tired of mouse acceleration and want to have a completely linear mouse response. This is easily achievable through any of the 5 or so methods (some subtly implied) on the X.Org wiki page on pointer acceleration. However, they also disable velocity scaling.

I don't want a 1:1 mapping between device and screen coordinates. I want a 1:N mapping where N is a constant. Any ideas?


Source: (StackOverflow)

Assigning USB hub to specific seat in multiseat configuration

On my debian-based machine, I have a working multiseat configuration.

One annoying detail that so far I couldn't fix is that any USB hardware I connect is always assigned to the primary seat.

Scouring the internet, it seems that the solution to this problem is to attach a USB hub to the machine and assign the "ownership" of it to the secondary seat. This way, any device attached to the hub will be controlled to the secondary seat. However, I'm a bit confused about how to assign the ownership.

lsusb allowed me to track the bus position of the hub:

Bus 002 Device 004: ID 1a40:0201 Terminus Technology Inc. Hub

I will be most grateful if somebody will guide me from here...

PS: Initially I thought I had to tweak the xorg.conf settings, but reading the conf.xorg documentation I couldn't find anything relevant. In some other post I also read about using udev, but again... I failed to find a clear how-to on how to achieve this.


Source: (StackOverflow)

How to stop the 'd' key from minimizing all windows in Ubuntu 10.10 when connected with Nomachine?

When I connect to my Ubuntu box from any Mac OS X 10.6 client (Snow Leopard) using Nomachine, the 'd' key minimizes all windows on my Ubuntu box. I found another post here that says the issue can be fixed by changing some settings on the Ubuntu box when connected. However, I cannot find the location of the settings indicated in that post.

Does anyone know how to resolve this 'd' key problem?


Source: (StackOverflow)

Xorg: How can I map AltGr to the CapsLock Key (to toggle 3rd level symbols)

as many others I don't need CapsLock. I want to reassign it such that it has the function of AltGr. I use Kubuntu 9.10 but I think there must be a solution which is distribution independent.

I already tried to use setxkbmap or xmodmap. Using xmodmap at least I managed that CapsLock to behaves like Del by following this description.

But I could not achieve assigning the AltGr behavior to CapsLock.


Source: (StackOverflow)

How to make Elo touchscreen working for Linux?

Elo touchscreen model:

  • Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r)

Problem description:

image description image description image description image description

  • My problem + others problem with this is that, when i touch-over (mouse-over) the touchscreen, the mouse cursor do not follow my (finger/touch) movement. On press the cursor press (click) in the wrong location.

My goal is to fix it, so that the press location is exact.

Tried

Following attempts i have done but no luck.

1) Query/Device status

--

udi = '/org/freedesktop/Hal/devices/usb_device_4e7_20_20B23159_if0_logicaldev_input'
  button.has_state = false  (bool)
  info.addons.singleton = {'hald-addon-input'} (string list)
  info.capabilities = {'input', 'button', 'input.mouse'} (string list)
  info.category = 'input'  (string)
  info.parent = '/org/freedesktop/Hal/devices/usb_device_4e7_20_20B23159_if0'  (string)
  info.product = 'Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface'  (string)
  info.subsystem = 'input'  (string)
  info.udi = '/org/freedesktop/Hal/devices/usb_device_4e7_20_20B23159_if0_logicaldev_input'  (string)
  input.device = '/dev/input/event11'  (string)
  input.originating_device = '/org/freedesktop/Hal/devices/usb_device_4e7_20_20B23159_if0'  (string)
  input.product = 'Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface'  (string)
  input.x11_driver = 'evdev'  (string)
  linux.device_file = '/dev/input/event11'  (string)
  linux.hotplug_type = 2  (0x2)  (int)
  linux.subsystem = 'input'  (string)
  linux.sysfs_path = '/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1:1.0/input/input11/event11'  (string)

2) Add a new file

$ vim /etc/X11/xorg.conf.d/elo.conf
Section "InputDevice"
    Identifier "touchscreen1"
    Driver "elographics"
    Option "Device" "/dev/ttyS0"
    Option "MinX" "470"
    Option "MaxX" "3670"
    Option "MinY" "600"
    Option "MaxY" "3550"
    Option "ScreenNumber" "0"
    Option "ReportingMode" "Scaled"
    Option "ButtonThreshold" "17"
    Option "ButtonNumber" "1"
    Option "SendCoreEvents"
EndSection

3) Logout to restart the X

4) Result is still same nothing was improved.

I appreciate your advise, on this.

Follow up:

$ cat /proc/bus/input/devices
I: Bus=0003 Vendor=04e7 Product=0020 Version=0100
N: Name="Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface"
P: Phys=usb-0000:00:1d.1-1/input0
S: Sysfs=/devices/pci0000:00/0000:00:1d.1/usb3/3-1/3-1:1.0/input/input6
U: Uniq=20B23159
H: Handlers=mouse1 event6 js0 
B: PROP=0
B: EV=1b
B: KEY=10000 0 0 0 0 0 0 0 0
B: ABS=100 3
B: MSC=10   
$ cat /dev/input/event6
$ xinput_calibrator -v --device 14 --precalib 0 1024 0 768 --output-type xinput
DEBUG: XInputExtension version is 2.0
DEBUG: Skipping virtual master devices and devices without axis valuators.
DEBUG: Selected device: Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface
DEBUG: Setting precalibration: 0, 1024, 0, 768
DEBUG: Not usbtouchscreen calibrator: Not a usbtouchscreen device
DEBUG: Read axes swap value of 0.
Calibrating EVDEV driver for "Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface" id=14
    current calibration values (from XInput): min_x=0, max_x=4095 and min_y=0, max_y=4095
DEBUG: Adding click 0 (X=1908, Y=731)

; ; Solved! section ;

$ yum search xinput; install xinput
$ xinput --help
usage :
    xinput get-feedbacks <device name>
    xinput set-ptr-feedback <device name> <threshold> <num> <denom>
    xinput set-integer-feedback <device name> <feedback id> <value>
    xinput get-button-map <device name>
    xinput set-button-map <device name> <map button 1> [<map button 2> [...]]
    xinput set-pointer <device name> [<x index> <y index>]
    xinput set-mode <device name> ABSOLUTE|RELATIVE
    xinput list [--short || --long] [<device name>...]
    xinput query-state <device name>
    xinput test [-proximity] <device name>
    xinput create-master <id> [<sendCore (dflt:1)>] [<enable (dflt:1)>]
    xinput remove-master <id> [Floating|AttachToMaster (dflt:Floating)] [<returnPointer>] [<returnKeyboard>]
    xinput reattach <id> <master>
    xinput float <id>
    xinput set-cp <window> <device>
    xinput test-xi2 <device>
    xinput list-props <device> [<device> ...]
    xinput set-int-prop <device> <property> <format (8, 16, 32)> <val> [<val> ...]
    xinput set-float-prop <device> <property> <val> [<val> ...]
    xinput set-atom-prop <device> <property> <val> [<val> ...]
    xinput watch-props <device>
    xinput delete-prop <device> <property>
    xinput set-prop <device> [--type=atom|float|int] [--format=8|16|32] <property> <val> [<val> ...]

; Hey how do i use xinput for query my stuffs?

$ xinput list
         ^
         |_______________ Show me what i got! for <input source> to my local

⎡ Virtual core pointer                      id=2    [master pointer  (3)]
⎜   ↳ Virtual core XTEST pointer                id=4    [slave  pointer  (2)]
⎜   ↳ Broadcom Corp                             id=10   [slave  pointer  (2)]
⎜   ↳ SynPS/2 Synaptics TouchPad                id=12   [slave  pointer  (2)]
⎣ Virtual core keyboard                     id=3    [master keyboard (2)]
    ↳ Virtual core XTEST keyboard               id=5    [slave  keyboard (3)]
    ↳ Video Bus                                 id=6    [slave  keyboard (3)]
    ↳ Power Button                              id=7    [slave  keyboard (3)]
    ↳ Sleep Button                              id=8    [slave  keyboard (3)]
    ↳ Broadcom Corp                             id=9    [slave  keyboard (3)]
    ↳ AT Translated Set 2 keyboard              id=11   [slave  keyboard (3)]
    ↳ Dell WMI hotkeys                          id=13   [slave  keyboard (3)]
⎡ main pointer                              id=15   [master pointer  (16)]
⎜   ↳ Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface   id=14   [slave  pointer  (15)]
⎜   ↳ main XTEST pointer                        id=17   [slave  pointer  (15)]
⎣ main keyboard                             id=16   [master keyboard (15)]
    ↳ main XTEST keyboard                       id=18   [slave  keyboard (16)]


$ xinput get-feedbacks 14
1 feedback class
PtrFeedbackClass id=0
    accelNum is 2
    accelDenom is 1
    threshold is 4

$ xinput watch-props 14
Device 'Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface':
    Device Enabled (150):   1
    Coordinate Transformation Matrix (152): 1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000
    Device Accel Profile (272): 0
    Device Accel Constant Deceleration (273):   1.000000
    Device Accel Adaptive Deceleration (274):   1.000000
    Device Accel Velocity Scaling (275):    10.000000
    Device Product ID (269):    1255, 32
    Device Node (270):  "/dev/input/event11"
    Evdev Axis Inversion (276): 0, 0
    Evdev Axis Calibration (277):   -4000, 4093, -100, 4089
    Evdev Axes Swap (278):  0
    Axis Labels (279):  "Abs X" (369), "Abs Y" (370), "Abs Misc" (580)
    Button Labels (280):    "Button Left" (153), "Button Unknown" (271), "Button Unknown" (271), "Button Wheel Up" (156), "Button Wheel Down" (157)
    Evdev Middle Button Emulation (281):    0
    Evdev Middle Button Timeout (282):  50
    Evdev Wheel Emulation (283):    0
    Evdev Wheel Emulation Axes (284):   0, 0, 4, 5
    Evdev Wheel Emulation Inertia (285):    10
    Evdev Wheel Emulation Timeout (286):    200
    Evdev Wheel Emulation Button (287): 4
    Evdev Drag Lock Buttons (288):  0

$ xinput query-state 14
2 classes :
ButtonClass
    button[1]=up
    button[2]=up
    button[3]=up
    button[4]=up
    button[5]=up
ValuatorClass Mode=Absolute Proximity=In
    valuator[0]=3018
    valuator[1]=3226
    valuator[2]=0

$ xinput test 14
motion a[0]=2940 a[1]=1717 a[2]=158 
motion a[0]=2940 a[1]=1717 a[2]=201 
button release 1 a[0]=2938 a[1]=1719 a[2]=0 
^C

; Hey, how do i apply now settings to my local using xinput??

$ xinput set-pointer <device name> [<x index> <y index>]
         ^
         |___this does not work anymore in latest kernels 
             report a bug it wasted my time

$ xinput set-int-prop "Elo TouchSystems, Inc. Elo TouchSystems 2700 IntelliTouch(r) USB Touchmonitor Interface" "Evdev Axis Calibration" 32 -4000 4093 -100 4089

Now, my right screen is having 1024x768 resolution and left laptop screen also, using the above statement, the mouse cursor is fitting well. If i have different resolutions, i need to finetune it ofcourse.


Source: (StackOverflow)