[Howto] solve “slow starting GTK applications”
problem: GTK applications need 25 seconds to start (info: 25s is the D-bus timeout) solution: uninstall the package xdg-dbus-proxy [edit 2023-09-10] uninstall the package xdg-desktop-portal-gnome
[Howto] upgrade DEBIAN if distribution name has changed
problem: if the name of the DEBIAN distribution has changed (e.g. testing-version changes from “bullseye” to “bookworm”), aptitude denies the update procedure. It requests a manual command to proceed. solution: execute the command apt-get update –allow-releaseinfo-change (it updates the file … Continued
[Howto] Raspberry Pi + I²C + MCP23017 + C (minimal example)
minimal working example: read data from MCP23017-register and print it to screen.
[Facts] Raspberry Pi + I²C + MCP23017: digital output toggle timespan (Bash, Python, C)
purpose: measuring the timespan between rising/falling-edge (=off/on/off-change) of a digital-output-bank (GPA0…GPA7) testing equipment: -Raspberry Pi 3 Modell B-I2C-adress of MCP23017-chip = 0x20-MCP23017 register-adress of 8 digital-outputs: 0x14-Owon SDS7102 digital ocsilloscope conclusion: I²C-baudrate bash Python C 100.000 5,18 ms @ 75 … Continued
[Howto] GTK+ and poppler (minimal example)
minimal working example, which creates a GTK-window and displays the first page of the given pdf-file.(compile with command: gcc example.c -o example `pkg-config –cflags –libs gtk+-3.0 poppler poppler-glib`) versions: GTK+ 3.24.23-2 and poppler-20.09.0-2
[Howto] GTK+ and cairo (minimal example)
minimal working example, which creates a GTK-drawing-area and draws ‘Test.’ inside.(compile with command: gcc example.c -o example `pkg-config –cflags –libs gtk+-3.0`) versions: GTK+ 3.24.23-2 and cairo 1.16.0-4
[FAQ] QElectroTech
Q: How to show power-contacts in contact-table?A: menu “project” –> menu-entry “project-properties” –> Tab “new folio” –> Tab “cross-references” –> type-entry “coil” –> enable “show the power contacts in the cross” Q: What is the difference between “label formula” and … Continued
[Howto] create a SSL/TLS certificate with LetsEncrypt (FreeBSD)
tested under FreeBSD v12.1 with certbot-1.3.0,1 install the let’s encrypt clientpkg install py37-certbot request your certificate (note: Port 80 must be unused, e.g. temporarily disable a running webserver)certbot certonly –standalone -d <your-domain> all done, now you will find your certificate … Continued
[Howto] OpenBox – default to maximized windows
The following configuration let openbox open all windows maximized per default: edit ~/.config/openbox/rc.xml and insert in the <applications>-tags: reconfigure running openbox (Desktop –> rightclick –> reconfigure) or restart openbox. Now all applications open in maximized windows. further informations: http://openbox.org/wiki/Help:Applications If … Continued
[Howto] save invalid bytes / characters in UTF-8 encoded database
situation:images are binary coded. If you try to interpret/decode them as UTF-8, they can contain UTF-8 invalid characters (e.g. 0xFF) problem:if your database uses the UTF-8 encoding, you can’t save this invalid bytes in this database. (“invalid byte sequence warning”) … Continued