CIRCULAR LOGIC- how does HOME work?

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geo_c
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CIRCULAR LOGIC- how does HOME work?

Post by geo_c »

Or put another way, how does HOME work in relation to a pupsave as a directory, is the link looking at the current HOME? It has to be, no?

I've done this before, but today I did it very intentionally trying to solve another issue described in this thread: viewtopic.php?f=4&t=3736

I decided to look inside one of my pupsave backups.

As I was examining the backup, I looked in mnt inside the pupsave, and again finding it, as it's a relative link, looked in that one. To help clarify what I'm saying, I'm posting a screenshot of a ROX window, with a very long directory that reads:

/mnt/home/jackalpup-frugal-LowLatency/jackalpupsave-613-i5.BKP-2021.0813-01.06/mnt/home/jackalpup-frugal-LowLatency/jackalpupsave-613-i5.BKP-2021.0813-01.06/mnt/home/

And I supposed I could continue like that until something breaks. And this is where my understanding of the circular reference breaks down. I'm looking for clarity, and perhaps this a Unix basic concept. But I like you guys' explanations better than what I can read on random websites.

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bigpup
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Re: CIRCULAR LOGIC- how does HOME work?

Post by bigpup »

I do not know why that is giving you such a long name for /mnt/home
jackalpup is a remaster of Fossapup64 9.5
Probably did not get everything in the remaster.
Does look like the save is in /jackalpup-frugal-LowLatency directory.

In Fossapup64 9.5 an official Puppy version.
/mnt/home is identified in Rox as /mnt/home

This is how to look at it.

/mnt/home is the location of the save file/folder.
Also usually where the frugal install is, because usually the save is with the frugal install.
In the mounting of locations, it is the always mounted location of the save.

the technical part.
/mnt/home is a symbolic link mount point link target to initrd/mnt/dev-save
When booting.
initrd does a process of looking for, mounting the save location, and it is to the layered operating filesystem initrd/mnt/dev-save, but shown in Rox as /mnt/home

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Re: CIRCULAR LOGIC- how does HOME work?

Post by puddlemoon »

Hi @geo_c
The circular motion is true in your example, you've just visited the same 4 locations twice and could keep going. The link /mnt/home/ always points to the root of the disk with the save as bigpup mentioned. So you could also go from one backed up (or current) save to the next, even with different pups, each one's /mnt will be unique but the "home" link will take you back to the same beginning. (which is more a serpentine motion I suppose with different saves)

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The long "address" in rox is a kind of history, so you can use the up arrow to work your way back step by step even if you've just gone in circles..
Of course none this is specific to jackalpup.

I think I understood your Q and I hope that helps a bit.

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Re: CIRCULAR LOGIC- how does HOME work?

Post by geo_c »

Thanks @puddlemoon and @bigpup

That clarifies. I was already catching on to the initrd/mnt/dev-save as being the actual mnt point, and home being the symbolic reference., simply because it shows up from time to time in certain app file browsers when saving and opening files.

In fact last night I decided to check out the contents of everything in initrd just to get a handle on things. What I saw were the same directories showing up in the pup_ro directories and figured that those are the layered file systems of sfs that are mounted.

Appreciate your time and energy fellas.

~geo

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Re: CIRCULAR LOGIC- how does HOME work?

Post by Jafadmin »

This isn't really about "/home'. It's about how symbolic links work, in general. Perform this experiment:

Create a directory called '/top' .. inside it create a new directory called 'level1' .. inside that create a directory called 'level2' .. and finally, inside that create a symbolic link to '/top'.

Code: Select all

/top
    level1
        level2
        	link_to_top

Then just keep clicking until the novelty wears off or you grow tired. :twisted:

You will walk away feeling smug that you now understand the difference between "circular logic" and "recursion" :thumbup2:

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