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    Please do not post a support request without first reading and following the advice in https://retropie.org.uk/forum/topic/3/read-this-first

    Environment variable DISPLAY is empty

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    displaypyautoguipython
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    • T
      teclisb
      last edited by

      Hi there!

      I wanted to do a kind of TAS for retropie and I'm stuck on an issue that I don't know how to solve.

      Here my install log

      sudo apt-get install python3-pip
      sudo apt-get install python3-xlib
      sudo pip3 install pyautogui

      Then I tried to launch a python Script through :

      sudo python3 /home/pi/RetroPie/test.py

      Traceback (most recent call last):
      File "test.py", line 22, in <module>
      import pyautogui
      File "/usr/local/lib/python3.5/dist-packages/pyautogui/init.py", line 115, in <module>
      from . import _pyautogui_x11 as platformModule
      File "/usr/local/lib/python3.5/dist-packages/pyautogui/_pyautogui_x11.py", line 160, in <module>
      _display = Display(os.environ['DISPLAY'])
      File "/usr/lib/python3.5/os.py", line 725, in getitem
      raise KeyError(key) from None
      KeyError: 'DISPLAY'

      I googled and found : https://stackoverflow.com/questions/49308345/how-to-fix-keyerror-display-in-python

      Which means there is no Display (echo $DISPLAY is empty)

      Why? Can I set one ? If someone knows... I would be happy to understand and learn!

      mituM 1 Reply Last reply Reply Quote 0
      • mituM
        mitu Global Moderator @teclisb
        last edited by mitu

        @teclisb RetroPie does not use an X11 environment when running on a Raspberry Pi and your program seems to need one in order to run. Only when installed on a PC, RetroPie runs from an X server session.
        Since you didn't add any of the info requested in https://retropie.org.uk/forum/topic/3/read-this-first, I'm not sure if this is the problem, but if you're trying to run this on a PI, then it won't work and you have to find a solution that doesn't need an X11 server started.

        1 Reply Last reply Reply Quote 0
        • T
          teclisb
          last edited by teclisb

          Pi Model or other hardware: Pi3
          Power Supply used: Yes and working well
          RetroPie Version Used (eg 3.6, 3.8.1, 4.1 - do not write latest): 4.4
          Built From: (Pre made SD Image on RetroPie website, Berryboot, or on top of existing OS etc.. - please provide the filename of any image used) : retropie-4.4-rpi2_rpi3.img
          USB Devices connected: XBOX360 Controller
          Controller used: XBOX360 Controller
          Error messages received: Previous message
          Log found in /dev/shm/runcommand.log (if relevant): Not relevant
          Guide used: (Mention if you followed a guide) None
          File: (File with issue - with FULL path) None
          Emulator: (Name of emulator - if applicable) None
          Attachment of config files: (PLEASE USE PASTEBIN.COM FOR LARGE LOGS) None
          How to replicate the problem: follow the previous installation and launch a python script using pyautogui

          Sadly pyautogui needs a X11, I tried the script on windows and it's working.
          Is there a way to start an X11 server and keep emulators working ?

          mituM 1 Reply Last reply Reply Quote 0
          • mituM
            mitu Global Moderator @teclisb
            last edited by

            @teclisb said in Environment variable DISPLAY is empty:

            Is there a way to start an X11 server and keep emulators working ?

            Only if you install RP on a PC, as I said before. Almost all emulators on the Pi version don't run on X, with some notable exceptions (mainly Ports).

            1 Reply Last reply Reply Quote 0
            • T
              teclisb
              last edited by

              Ok I see... So it's possible to use my script and retropie However, only on a computer.
              Thanks for the information I wasn't aware that on RP almost all emulators don't run on X.

              Thanks a lot :)

              1 Reply Last reply Reply Quote 0
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