fix readme

README.md

@@ -105,18 +105,118 @@ sudo cp config/config.json /opt/buttontask/config/
 # privileged helpers (root-owned) + sudoers whitelist
 sudo install -m 0755 webconfig/scripts/bt-netconfig webconfig/scripts/bt-update \
                      webconfig/scripts/bt-service /opt/buttontask/scripts/
-sudo install -m 0440 webconfig/scripts/buttontask.sudoers /etc/sudoers.d/buttontask
+sudo tee /etc/sudoers.d/buttontask > /dev/null << 'EOF'
+buttontask ALL=(root) NOPASSWD: /opt/buttontask/scripts/bt-netconfig
+buttontask ALL=(root) NOPASSWD: /opt/buttontask/scripts/bt-update
+buttontask ALL=(root) NOPASSWD: /opt/buttontask/scripts/bt-service
+EOF
+sudo chmod 0440 /etc/sudoers.d/buttontask
 sudo visudo -cf /etc/sudoers.d/buttontask
 
 sudo chown -R buttontask:buttontask /opt/buttontask
 sudo chown root:root /opt/buttontask/scripts/bt-*   # scripts must be root-owned
 
+# Qt eglfs needs a writable runtime dir for the unprivileged user
+sudo mkdir -p /tmp/runtime-buttontask
+sudo chown buttontask:buttontask /tmp/runtime-buttontask
+sudo chmod 0700 /tmp/runtime-buttontask
+
+# eglfs grabs KMS/DRM directly; disable the desktop display manager
+sudo systemctl disable display-manager
+sudo systemctl stop display-manager
+
 sudo cp webconfig/buttontask.service /etc/systemd/system/
 sudo cp webconfig/buttontask-web.service /etc/systemd/system/
 sudo systemctl daemon-reload
 sudo systemctl enable --now buttontask buttontask-web
+
+# verify sudoers (should succeed without a password prompt)
+sudo -u buttontask sudo -n /opt/buttontask/scripts/bt-netconfig eth0 dhcp
 ```
 
+### Touchscreen (device-specific override)
+
+The base `buttontask.service` does not hardcode a touch device path because the
+`eventN` number varies between boards. Copy the example override and set the
+correct event for your touchscreen:
+
+```sh
+# find the touchscreen event number
+grep -l -E 'ABS_X|ABS_MT_POSITION' /sys/class/input/event*/device/capabilities/abs 2>/dev/null \
+  | sed 's|.*/input/event||;s|/device.*||'
+
+sudo mkdir -p /etc/systemd/system/buttontask.service.d
+sudo cp /opt/buttontask/current/webconfig/buttontask.service.d/override.conf.example \
+        /etc/systemd/system/buttontask.service.d/override.conf
+# edit override.conf — replace event1 with the number found above
+sudo systemctl daemon-reload && sudo systemctl restart buttontask
+```
+
+### Migrating an already-deployed device
+
+If the device was installed from an older guide, apply these fixes:
+
+```sh
+# 1. sudoers (fixes "sudo: a password is required" in web network config)
+sudo tee /etc/sudoers.d/buttontask > /dev/null << 'EOF'
+buttontask ALL=(root) NOPASSWD: /opt/buttontask/scripts/bt-netconfig
+buttontask ALL=(root) NOPASSWD: /opt/buttontask/scripts/bt-update
+buttontask ALL=(root) NOPASSWD: /opt/buttontask/scripts/bt-service
+EOF
+sudo chmod 0440 /etc/sudoers.d/buttontask
+sudo visudo -cf /etc/sudoers.d/buttontask
+
+# 2. runtime dir
+sudo mkdir -p /tmp/runtime-buttontask
+sudo chown buttontask:buttontask /tmp/runtime-buttontask
+sudo chmod 0700 /tmp/runtime-buttontask
+
+# 3. display manager
+sudo systemctl disable --now display-manager
+
+# 4. updated unit + touch override (see above)
+sudo cp /opt/buttontask/current/webconfig/buttontask.service /etc/systemd/system/
+sudo systemctl daemon-reload
+
+# 5. icons — until OTA with the path-resolution fix, set absolute iconsDir:
+#    "iconsDir": "/opt/buttontask/icons" in /opt/buttontask/config/config.json
+
+sudo systemctl restart buttontask-web buttontask
+```
+
+### Troubleshooting
+
+**`/usr/bin/env: 'bash\r': No such file or directory`**
+
+Shell scripts were saved with Windows CRLF line endings. On the device, fix in place:
+
+```sh
+sudo sed -i 's/\r$//' /opt/buttontask/scripts/bt-*
+```
+
+Or re-copy the scripts from a repo checkout with LF endings (see `.gitattributes`).
+
+**`sudo: a password is required` (web → Сеть)**
+
+- `sudo visudo -cf /etc/sudoers.d/buttontask` must pass without errors
+- web service must run as `buttontask`: `systemctl show -p User buttontask-web`
+- helper scripts must be root-owned: `ls -la /opt/buttontask/scripts/bt-*`
+- test manually: `sudo -u buttontask sudo -n /opt/buttontask/scripts/bt-netconfig eth0 dhcp`
+
+**`QML Image: Cannot open: file:///./icons/...`**
+
+- Icons are stored in `/opt/buttontask/icons/` (shared, outside the version dir)
+- Set `"iconsDir": "/opt/buttontask/icons"` in config, or deploy a build with
+  the C++ path-resolution fix (relative `./icons` is resolved against
+  `BUTTONTASK_ROOT`, same as the web configurator)
+
+**Touch not working**
+
+- Check the override at `/etc/systemd/system/buttontask.service.d/override.conf`
+- Re-detect the event number (see Touchscreen section above)
+- Ensure the `buttontask` user is in supplementary groups `video render input`
+  (set in `buttontask.service`)
+
 ## Network configuration (Ethernet)
 
 Open the web UI → tab **Сеть**. It reads the live state via `nmcli` and can
@@ -173,7 +273,7 @@ live and is also readable in the app's **Обновление** page.
     "darkMode": true,
     "password": "admin",     // shared with web auth
     "kioskMode": false,
-    "iconsDir": "./icons",   // dir for user icons & background images
+    "iconsDir": "/opt/buttontask/icons",   // dir for user icons & background images
     "webPort": 8080
   },
   "buttons": [