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by plugwash
Wed May 29, 2019 12:30 pm
Forum: Python
Topic: I need an import guru
Replies: 3
Views: 453

Re: I need an import guru

No, each module is only loaded once, even if it is imported from multiple places.
by plugwash
Wed May 29, 2019 12:08 pm
Forum: Python
Topic: I need an import guru
Replies: 3
Views: 453

Re: I need an import guru

Yes, it's normal. Broadly speaking "import" does two things. 1. Loads modules if they are not already loaded. 2. Binds names so that you can access stuff from those modules. Each module in your program (including the main program itself, which is regarded by the interpreter as a module named __MAIN_...
by plugwash
Tue May 28, 2019 8:37 pm
Forum: Other programming languages
Topic: Introduction to BBC BASIC
Replies: 579
Views: 43852

Re: Introduction to BBC BASIC

This is all very dodgy territory. Turning on optimization should not change the behavior of a program. Except of course if the source is depending on behavior that is undefined by the C standard. Which it is in this case. IIRC the C standard has a massive caveat that even a well-formed program may ...
by plugwash
Tue May 21, 2019 8:28 pm
Forum: Raspbian
Topic: introducing raspbmirror, the new way to mirror the raspbian archive.
Replies: 10
Views: 1224

Re: introducing raspbmirror, the new way to mirror the raspbian archive.

hippy wrote:
Mon May 20, 2019 2:29 pm
Because you piqued my curiosity, caused an eyebrow to be raised; how large is a full Raspbian mirror download ?
330G currently.
by plugwash
Mon May 20, 2019 11:41 am
Forum: Raspbian
Topic: introducing raspbmirror, the new way to mirror the raspbian archive.
Replies: 10
Views: 1224

Re: introducing raspbmirror, the new way to mirror the raspbian archive.

what filesystem is your external hdd using? I suspect your problem is you are trying to mirror onto a filesystem that does not support symlinks.
by plugwash
Thu May 16, 2019 6:32 pm
Forum: HATs and other add-ons
Topic: What is this?
Replies: 2
Views: 502

Re: What is this?

It's a shielding can. With the raspberry pi 3 model B the board was EMC certified as an end product. That was fine for end-users but it created problems for people wanting to use the Pi as part of a larger product. They essentially had to do the full "intentional radiator" EMC tests again. To make l...
by plugwash
Wed May 15, 2019 1:23 am
Forum: Raspbian
Topic: legacy materials moving from archive.raspbian.org to legacy.raspbian.org
Replies: 5
Views: 2097

Re: legacy materials moving from archive.raspbian.org to legacy.raspbian.org

I got distracted by other things and a week or so turned into a month and a half, but the legacy materials have now finally been removed.
by plugwash
Thu May 09, 2019 12:50 am
Forum: Troubleshooting
Topic: May 2019: No package 'readline' found
Replies: 1
Views: 178

Re: May 2019: No package 'readline' found

hmm, I can't find any evidence of there ever being a readline.pc in debian, though I did find wishlist a bug report requesting it be added. https://bugs.debian.org/cgi-bin/bugrepo ... bug=901650

What software are you trying to build?
by plugwash
Mon May 06, 2019 6:26 pm
Forum: Off topic discussion
Topic: An Apology to Alan
Replies: 8
Views: 1006

Re: An Apology to Alan

BBC basic keywords were all caps, but you could use lower case in variable names, strings etc.
by plugwash
Thu May 02, 2019 5:07 pm
Forum: Python
Topic: List Behavior Changes Depending on Initialization?
Replies: 4
Views: 337

Re: List Behavior Changes Depending on Initialization?

In python pretty much everything is an object, to which there can be one or more references. A python list is an object representing a mutable list of references to objects. With your first statement you create 17576 innermost lists, 676 lists at the next level out, 26 lists at the next level out fr...
by plugwash
Tue Apr 30, 2019 12:25 am
Forum: Raspbian
Topic: introducing raspbmirror, the new way to mirror the raspbian archive.
Replies: 10
Views: 1224

Re: introducing raspbmirror, the new way to mirror the raspbian archive.

Currently it will knock off about 20 gigs from the download, which isn't all that much in the grand scheme of things, this figure may change as non-repo materials are removed and/or added from archive.raspbian.org I want to add support for mirroring only a subset of suites, but that requires some mo...
by plugwash
Mon Apr 29, 2019 11:50 pm
Forum: Raspbian
Topic: introducing raspbmirror, the new way to mirror the raspbian archive.
Replies: 10
Views: 1224

Re: introducing raspbmirror, the new way to mirror the raspbian archive.

yeah it's a bug. There is a related script "downloadsnapshot" aimed at a different usecase from raspbmirror (raspbmirror is aimed at maintaining a mirror, downloadsnapshot is aimed at maintaining a series of hardlink based snapshots). It seems I have the tlwhitelist feature in downloadsnapshot but n...
by plugwash
Thu Apr 25, 2019 5:23 pm
Forum: Raspberry Pi Desktop for PC and Mac
Topic: Raspberry Pi Desktop not fully updateable!
Replies: 4
Views: 557

Re: Raspberry Pi Desktop not fully updateable!

Remove the line mentioning jessie-updates from /etc/apt/sources.list
by plugwash
Tue Apr 23, 2019 10:24 pm
Forum: Advanced users
Topic: Secured Pi2 sending unsolicited traffic to unfamiliar IP's
Replies: 3
Views: 350

Re: Secured Pi2 sending unsolicited traffic to unfamiliar IP's

Apr 23 07:26:07 raspberrypi kernel: [119344.479539] [UFW BLOCK] IN= OUT=eth0 SRC=192.168.0.12 DST=218.92.1.130 LEN=52 TOS=0x00 PREC=0x00 TTL=64 ID=40471 DF PROTO=TCP SPT=22 DPT=38541 WINDOW=493 RES=0x00 ACK PSH FIN URGP=0 This looks like your ssh server trying to respond to a connection attempt. No...
by plugwash
Tue Apr 23, 2019 7:59 pm
Forum: Arch
Topic: https://forum.manjaro.org/t/manjaro-arm-19-02-released/75594
Replies: 49
Views: 15779

Re: Manjaro dropping ARMv7 support

Umm why are you quoting something I quoted and debunked as if I said it?
by plugwash
Tue Apr 23, 2019 6:21 pm
Forum: Arch
Topic: https://forum.manjaro.org/t/manjaro-arm-19-02-released/75594
Replies: 49
Views: 15779

Re: Manjaro dropping ARMv7 support

There is no myth in the 32 bit 2038 in the Linux kernel. It's not a myth, but it's not an insurmountable problem either. x32 ABI was a sort of 32->64bit bridge and its been depreciated x32 was an attempt at making an ABI which ran the processor in 64 bit mode but had 32 bit pointers, as you say it ...
by plugwash
Tue Apr 23, 2019 2:10 pm
Forum: Arch
Topic: https://forum.manjaro.org/t/manjaro-arm-19-02-released/75594
Replies: 49
Views: 15779

Re: Manjaro dropping ARMv7 support

Such an architecture could certainly be built in theory, but it would require substantially more instructions for every address calculation. Worse, for a modern pipelined CPU those instructions have tight dependencies on each other. Given how cheap transistors are nowadays it makes little sense to w...
by plugwash
Sat Apr 20, 2019 1:00 am
Forum: Beginners
Topic: Defective ports?
Replies: 9
Views: 461

Re: Defective ports?

This is normal, connectors have some allowance for mounting in a case, so when using a bare board they stick out a bit.
by plugwash
Tue Apr 16, 2019 12:42 pm
Forum: Camera board
Topic: Why no 4-lane CSI on the Zero?
Replies: 2
Views: 338

Re: Why no 4-lane CSI on the Zero?

While I don't know for sure I strongly suspect it was PCB routing difficulties. The CM has extra layers (8 rather than 6 iirc) to allow them to bring out every pin on the chip.
by plugwash
Tue Apr 16, 2019 11:43 am
Forum: Other programming languages
Topic: Introduction to BBC BASIC
Replies: 579
Views: 43852

Re: Introduction to BBC BASIC

Note that while arm decided to make long double 128 bits in their arm64 ABI, no current arm core has support for 128 bit floating point in hardware. So "long double" calculations on arm64 will be done with a software implementation.
by plugwash
Sun Apr 07, 2019 4:02 pm
Forum: Python
Topic: keep only newest 50 directories and delete older ones
Replies: 3
Views: 578

Re: keep only newest 50 directories and delete older ones

In python slicing negative indexes count from the end of the object being sliced (indeed you make use of this feature elsewhere in your code). So when your subtraction returns a value of -23, python interprets that as "give me everything except the last 23 items", which leaves four items to delete. ...
by plugwash
Fri Apr 05, 2019 11:12 pm
Forum: General discussion
Topic: Is this a real raspberry pi?
Replies: 8
Views: 1026

Re: Is this a real raspberry pi?

Farnell offer a customisation service for raspberry pi, where those buying large numbers of Pis can have tem customised. it appears that kano have used it to produce a custom cost-reduced Pi 3 model with the DSI and CSI connectors unpopulated and with a basic 4-port USB hub instead of the (relativel...
by plugwash
Fri Apr 05, 2019 2:17 am
Forum: HATs and other add-ons
Topic: My PoE hat has undergone electrical damage somehow
Replies: 3
Views: 433

Re: My PoE hat has undergone electrical damage somehow

The original PoE hat had insufficient output filtering and was interacting badly with the USB power protection on some Pi boards (apparently there were two different chips used for power protection and one was more sensitive to the issue than the other). To fix this the boards were re-worked to add ...
by plugwash
Thu Apr 04, 2019 7:43 pm
Forum: Raspbian
Topic: legacy materials moving from archive.raspbian.org to legacy.raspbian.org
Replies: 5
Views: 2097

legacy materials moving from archive.raspbian.org to legacy.raspbian.org

As you may be aware Debian wheezy has now been fully end of lifed (including lts) by Debian. As a result I am moving a number of legacy and mostly wheezy-related materials from archive.raspbian.org to legacy.raspbian.org. This includes the complete contents of the following directories. images insta...
by plugwash
Thu Apr 04, 2019 7:39 pm
Forum: Off topic discussion
Topic: Why Avoid BASIC on RPi?
Replies: 2312
Views: 121457

Re: Why Avoid BASIC on RPi?

I think the biggest problem BASIC has is people assume it's another BBC retro language with no practicl use in today's world. No, the biggest problem basic has is it's not one language, it's a heap of incompatible languages. Some require line numbers, some have optional line numbers, some don't sup...

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