[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
[Howto] input UTF-8 characters in GTK applications
hold-down ‘CTRL+SHIFT+u’, then input the UTF-8 character-code and then press enter.
[Howto] GTK3 with CSS (minimal example)
It is a working example for a button, which changes its color while mouse-over. gtk-version: 3.24.12-1 note: the css-property “background-image: none” is sometimes mandatory, because the default theme prevents displaying the css-defined background-color. The workaround is to set the … Continued
[Howto] FreeBSD v12 and TP-Link TL-WN725N WLAN-Stick
OS: FreeBSD 12.0-RELEASE-p4 amd64 WLAN hardware: TP-Link TL-WN725N (builtin REALTEK RTL8188EU chipset) insert the USB WLAN-stick to your computer check, if the kernel recognizes the usb-stick: dmesg and check the output load the corresponding kernel-modules: kldload rtwn.ko and kldload if_rtwn_usb.ko … Continued
[Howto] solve login-error message “init[]: getty repeating too quickly on port /dev/ttyv0, sleeping 30 secs”
the problem is a malfunction, because the file /etc/ttys has a wrong configuration. Everytime this error message appears, the login-process is restarted and any established sessions are restarted (=new login-Prompt). Afaik it’s a result of checking for serial devices and … Continued
[Howto] solve “lost connection with [private/dovecot-lmtp] while sending end of data”-error
if you use postfix and dovecot via LMTP you can get the following error messages: #postfix.logstatus=deferred (lost connection with <xxxxxxxxx> [private/dovecot-lmtp] while sending end of data — message may be sent more than once#dovecot.logFatal: master: service(lmtp): child 76549 returned error … Continued
[Howto] enable column sorting in GTK+ views
it’s very simple, because you must only define a “sort-column-id” for the column (GTK Version 3.24.5-1) # define sort-column-id for a specific columngtk_tree_view_column_set_sort_column_id(GTK_TREE_VIEW_COLUMN(firstcolumn), 0) This function enables a “clickable column-header” and sorting (default: switches with every click between ascending/descending sortorder) … Continued
[Howto] enter unicode characters in linux
Hold down “Ctrl + Shift”, type “u” followed by the “unicode-number” and then release “Ctrl+Shift”. for example: “✔” will be inserted with
[Howto] speed-up a slow gtk_tree_view (GTK3)
problem: every time, when the model-data inside the GTK_TREE_VIEW is changed/updated, the whole view will be recalculated (e.g. auto-sizing of row height and column width). This behaviour can lead to massive cpu load and time consumption, because the recalculation will … Continued