Necessity of a save file

[snayak]

Hi,

Just wanted to know...

What is the real necessity of a save file ?
and that too in ext3/linux file format?
Can't we fulfil the necessity of save file with a normal directory?

I mean, at any case we have a filelist for applications that are installed.
They can be uninstalled consulting this filelist. And apps can be run from a directory.
So if we keep a directory for installing outside apps, with a mimic of linux filesystem (I mean, with /root, /mnt, /dev, /etc folders etc.), will it be not enough?

I am not sure what other things make a save file mandatory.
However, I just got an idea, "why it is not possible...".
Please help.


Sincerely,
Srinivas Nayak

[disciple]

Hi,

Just wanted to know...

What is the real necessity of a save file ?
and that too in ext3/linux file format?
Can't we fulfil the necessity of save file with a normal directory?

I think it would be possible to use a folder. But not in a Windows filesystem*, and it is important for new Puppy users to be able to have full functionality even when they don't have a partition with a Linux filesystem (or a multisession Puppy CD/DVD).

* The main Linux filesystem really should be in a format that supports symlinks and is case sensitive. Take a look at all the symlinks in /usr/lib and you'll see why. If you used a Windows filesystem when you installed a package with a lib and it wanted to create a symlink it would create a copy instead. This would be a waste of disk space and a pain when you later wanted to move to a Linux filesystem.
... although there is/was a special distro designed to install in a VFAT filesystem - I'm not sure what special things they did to make it work.

[snayak]

Dear Disciple,

It is good to hear that it is possible with FAT file system.
However, the point you have shown (...symlink...) is also a point to ponder.
Can't we make a symlink in a fat file system that is mounted to linux?

Can you please let me know the distro (installable on VFAT) name?

I didn't get

...it is important for new Puppy users to be able to have full functionality even when they don't have a partition with a Linux filesystem (or a multisession Puppy CD/DVD).

Can you please clarify this?

Sincerely,
Srinivas

[disciple]

Dear Disciple,

It is good to hear that it is possible with FAT file system.
However, the point you have shown (...symlink...) is also a point to ponder.

Can't we make a symlink in a fat file system that is mounted to linux?

There was a patch for at least some of the 2.4 series Linux kernels which abused Windows .lnk files to act as symlinks. So in theory that would be possible, but as far as I know the patch has not been ported to a 2.6 kernel.
Wine doesn't really work with a 2.4 series kernel if people want to use it; I don't know of any other programs that have a problem with it.
I suspect there is a reasonable amount of modern hardware that you can't use with a 2.4 kernel.
And it might be quite a lot of work to build a modern Puppy with a 2.4 kernel (Puppy has had a 2.6 kernel since Puppy 2. When running Puppy 1.x from a live CD or a frugal install only /root is writeable, not /, because limitations of unionfs in the 2.4 kernel don't allow it).
I'm not really sure how real an issue it is that Windows filesystems are not truly case sensitive.
The other thing that I forgot to mention is that Windows filesystems don't support the same attributes as normal filesystems; in particular there is no "executable bit" - on a VFAT partition everything is "executable" to everybody. I don't think this is too much of a practical problem for Puppy, but it will get the tin foil hat people even more up in arms, and I think again it would be a rather "Bad Thing" when the user later wants to move to a normal filesystem.

Can you please let me know the distro (installable on VFAT) name?

It looks like there's one called Doslinux, but I don't know that it's the one I was thinking of.

[Karl Godt]

Nice idea, might work if the puppy_main.sfs is installed to some of the linux file systems .

The problem is that there are several layers for unionfs or aufs with the savefile on bottom and then the main_puppy_sfs, the zdrv.sfs, [adrv.sfs if saluki,] devx.sfs, other program_modules.sfs -- referring /initrd/pup_ro1 as bottom layer .

On flash (odd pupmodes like 3,7,13) there is another bottommost rootfs layer as tmpfs as a write to disk buffer .

I have no idea how to merge a folder into the combined rootfs layers . A folder seems not to have a limitation in size , could easily eat up much ...