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From the replies :)

> In CS theory, regular languages are a strict subset of context-free languages, but regular expression implementations in mainstream programming languages are more powerful. As noulakaz.net/weblog/2007/03/18/… describes, so-called "regular expressions" can check for prime numbers in unary, which is certainly something that a regular expression from CS theory can't accomplish. – Adam Mihalcin Commented Mar 19, 2012 at 23:50


Been thinking of getting one of these but was worried about the proprietary app. I guess I have no reason now : )

There are a few open projects to support a lot of these thermal cams like the more popular Topdon or InfiRay models. PyThermalCamera [0] or Thermal-Camera-Redux [1] are good ones, I got my thermal cam working on my Linux laptop just fine.

[0] https://github.com/leswright1977/PyThermalCamera

[1] https://github.com/92es/Thermal-Camera-Redux


Do you know of anything that can handle UNI-T cams, particularly something like UTi721M, which is a nice thermal cam that attaches to a smartphone via USB-C?

Eevblog forum is the original source for most of the Github projects around these thermal cams. So that's a good place to start.

https://www.eevblog.com/forum/thermal-imaging/new-software-f...

https://github.com/Santi-hr/UNI-T-Thermal-Utilities


I run rdfind[1] as a cronjob to replace duplicates with hardlinks. Works fine!

https://github.com/pauldreik/rdfind


So this is great, if you're just looking to deduplicate read only files. Less so if you intend to write to them. Write to one and they're both updated.

Anyway. Offline/lazy dedup (not in the zfs dedup sense) is something that could be done in userspace, at the file level on any filesystem that supports reflinks. When a tool like rdfind finds a duplicate, instead of replacing with a hardlink, create a copy of the file with `copy_file_range(2)` and let the filesystem create a reflink to it. Now you've got space savings and they're two separate files so if one is written to the other remains the same.


How would this work if I have snapshots? Wouldn’t then the version of the file I just replaced still be in use there? But maybe I also need to store the copy again if I make another snapshot because the “original “ file isn’t part of the snapshot? So now I’m effectively storing more not less?

AFAIK, yes. Blocks are reference counted, so if the duplicate file is in a snapshot then the blocks would be referenced by the snapshot and hence not be eligible for deallocation. Only once the reference count falls to zero would the block be freed.

This is par for the course with ZFS though. If you delete a non-duplicated file you don't get the space back until any snapshots referencing the file are deleted.


Yes that snapshots incur a cost I know. But I’m wondering whether now the action of deduplicating actually created an extra copy instead of saving’one.

I don't fully understand the scenario you mentioned. Could you perhaps explain in a bit more detail?

copy_file_range already works on zfs, but it doesn't guarantee anything interesting.

Basically all dupe tools that are modern use fideduprange, which is meant to tell the FS which things should be sharing data, and let it take care of the rest. (BTRFS, bcachefs, etc support this ioctl, and zfs will soon too)

Unlike copy_file_range, it is meant for exactly this use case, and will tell you how many bytes were dedup'd, etc.


But then you have to be careful not to remove the one which happens to be the "original" or the hardlinks will break, right?

No, pointing to an original is how soft links work.

Hard links are all equivalent. A file has any number of hard links, and at least in theory you can't distinguish between them.

The risk with hardlinks is that you might alter the file. Reflinks remove that risk, and also perform very well.


Thank you, I was unaware of this.

However, the fact that editing one copy edits all of them still makes this a non-solution for me at least. I'd also strongly prefer deduping at the block level vs file level.


I would suspect a call to $(chmod a-w) would fix that, or at least serve as a very fine reminder that there's something special about them

Quite cool, though it's not as storage saving as deduplicating at e.g. N byte blocks, at block level.

At least for android apps, it's best to first rate 5 stars, then the lower score in Play store, as those pop-ups usually only redirect to play store for high ratings, to inflate their rank.

These are happening this time of the year where I live. I like to go out at sunset to watch them dance. It's amazing how they coordinate so well at such close quarters, looks like a single organism from afar.


Can you give an example?

EDIT: Just seen your other reply. Perhaps it was excluded due to right to forget laws?


If you ask them they will remove sites that you created. It's not under right to forget laws as they don't exist in the US. What I'd like to know is whether they also delete the data or just make it inaccessible.


ploetzblog was available and is now completly gone :( "lost" some recipes that he didn't migrate that I used to bake all the time. Used to look it up on the IA and was pissed when it was deleted


Same experience in Portugal. I've only had a dental x-ray before removing wisdom teeth.


Anyone that has a real need for something like that is either using either very specialized (and expensive) hardware, or some peripheral solution like TFA. We already have general purpose, mass produced devices that benefit from huge scale, and there's no such scale in amateur radio.


In some cases, the model will be lighter. There is no need for 14M parameters for physics simulations, and there's a lot of promising work in that area.


I wouldn't be so quick to dismiss such comparisons. Fiction can be a great tool to explore very real truths.


They are still fictions. You can use them as "what ifs", but not as an argument for "what happened".


Alpha wolves only exist in captivity.


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