[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
[Facts] ZFS RAID-Z2 scrubbing speed
8-core CPU Intel Xeon E5-2665 64 GB DDR3 ECC RAM OS FreeBSD 11.212x hdd’s RAID-Z2 (5400 rpm, SATA-2, consumer-grade) 2x ssd’s L2ARC (SATA-2, consumer-grade) 1x ssd SLOG (SATA-2, consumer-grade) pool specs: 81% full, 40% fragmentationscrub CPU-load: 60..75 % on all … Continued
[Howto] GTK+ FileChooser-dialog example
GTK+ 3 example: open filechooser-dialog with 2 buttons, select file, click open, print filename to console, clear filename-memory, close filechooser-dialog GtkWidget *fc_dialog;GtkFileChooser *fc;char *filename;fc_dialog = gtk_file_chooser_dialog_new(“Title”, NULL, GTK_FILE_CHOOSER_ACTION_OPEN, “Abort”, GTK_RESPONSE_CANCEL, “Open”, GTK_RESPONSE_ACCEPT, NULL);gtk_widget_show(fc_dialog);if (gtk_dialog_run(GTK_DIALOG(fc_dialog)) == GTK_RESPONSE_ACCEPT){ fc = GTK_FILE_CHOOSER(fc_dialog); filename … Continued
[Howto] play h265 (hevc) 10-bit video with hardware acceleration
recommendations: #check, if VDPAU-API is working (h.265 = HEVC.MAIN decoder profile must be supported) vpdauinfo #check, if VA-API is working (h.265 ‘entrypoints’ must be listed) vainfo problem: vdpau-driver doesn’t support h.265 10-bit hardware-decoding yet. It falls back to software decoding … Continued
[Facts] cpu + gpu hardware acceleration speedup (h.264, h.265, vdpau, vaapi)
system: kernel: linux-4.16.0-1-amd64 mediaplayer: vlc-3.0.3 cpu: intel i3-4160 (2 Threads/2 Cores, 3600 MHz) gpu: amd radeon hd 7950 (r9-280, tahiti-core) tool: top-3.3.15 measured values (average cpu-usage with top): h.264 (MPEG-4 AVC Part 10) 1920×1080 @ 23,976 fps only cpu-usage … Continued
[Howto] start X without systemd requirement
situtation: debian’s X-Server requires a systemd-session to work. problem: If you haven’t installed systemd, you aren’t able to start the xserver, because the xserver can’t connect to an systemd session. (EE) systemd-logind: failed to get session: The name org.freedesktop.login1 was not provided … Continued
[Howto] resolve LaTeX error message “Cannot determine size of graphic xxx (no BoundingBox)”
problem: LaTeX-Compiler can’t determine the graphic-size, because there is no such information in the graphics-file. Error messages like: “Cannot determine size of graphic <picture> (no BoundingBox)” solution: use a graphic fileformat, which saves picture-size information, e.g. *.eps OR use … Continued
[Howto] dhcpd and DDNS Update without hostname: expression to create a hostname
ISC dhcpd 4.3.6 ISC bind 9.10.6-p1 Problem: dhcpd requires a client-hostname to update the DNS zone dynamically (=DDNS). If the client doesn’t send a hostname (or the hostname is empty), dhcpd can’t add an DNS entry dynamically in the … Continued
[Howto] rc.d start script examples in FreeBSD
FreeBSD v11.1 service control: #to start, stop, restart, reload config or show status of a service execute: service <name> start service <name> stop service <name> restart service <name> reload service <name> status create the following scripts in the … Continued