February 10 2026 CUPS, KDE Plasma, Unix time, FFmpeg, slide rule emulations
John asked about a problem when accessing CUPS on Linux Mint which a friend had encountered; Firefox had warned him that the connection was not secure — something John had never encountered. David said it was Firefox expecting an https connection and he should just click on the blue button to allow him to proceed.
Darren had had a number of crashes with KDE Plasma; John wondered if he needed to try Wayland but David said it was more likely to be an incompatibility between Qt versions or a hardware problem such as a video card or memory module needing reseating. Following further discussion, it became clear that Darren was running Slackware Current and David recommended a complete update of Current and, if the problem persisted, then to investigate possible hardware problems.
David picked up a conversation about Unix time which had taken place on the mailing list. He had established that the creators of Unix had used a PDP11 which didn’t have a realtime clock; you had to pay money to get a clock which gave you an interrupt every 50th or 60th of a second dependent on the mains frequency.
The creators of Unix gave Unix time a signed integer for ease of calculation but unsigned integers were in practice not that common at the time. There were unsigned integers in PL/1 but they tended not to be used until the arrival of minicomputers.
Multics had 72bit microsecond precision but nothing could use it.
None of these systems relied on a realtime clock; they relied on the operator typing the date and time correctly. VAXs had a PDP11 operating as a console where you would enter the date and time. The VAX firmware was on a floppy which you put into the PDP11. VAX VMS had microfortnights, approximately 1 second, which were used to define the time it waited for the operator to type in the date and time.
David mentioned that, in view of the exorbitant cost of storage, he was converting his videos from H.264 to H.265 to save space but was bemused by the complexity of the FFmpeg command line; the process needed scripting. It also took a long time to convert each video.
Bernard mentioned that he had been looking at slide rule emulations written in Javascript.
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