using a 3rd partition on a USB thumb drive as standard USB memory stick?
Greetings, puppypeople. I tried to start using FossaPup a year ago and then got distracted. I am back at it again. I would like to make a USB drive that can boot FossaPup on one laptop but then transfer the files I am working on to other computers. In other words, I don't want to save to the SaveFile but to a separate partition. I successfully did this using two USB sticks--one to boot FossaPup and one to save files to--I could transfer files between FossaPup and another computer running Lubuntu. However, I would really like to have the third partition on the boot USB, so I only have to use one USB stick.
Using GParted, I created an "msdos" partition table. Partition 1 is 300MB fat32 boot, partition 2 is 4GB ext4 FossaPup, and partition 3 (sda3) is 3.5GB ext4.
In FossaPup, I can save to sda3 by mounting it and then selecting it in "/mnt/sda3".
However, in Lubuntu, I cannot save to sda3. I can open the files I saved in FossaPup and then do "Save as..." to my Lubuntu desktup, but I cannot write on sda3 at all.
I have looked at GParted and another Disc program to see if there were any permissions I could change on sda3, but I don't see anything. The only thing I can think of is that the USB has to be "gpt" rather "msdos" in order for Lubuntu to write to it. However, that is a problem because, when I make a "gpt" partition table, the laptop I want to run FossaPup on will not boot FossaPup (I can select the "UEFI namename, partition 1" at F12 screen, however when I select it and hit enter, it just boots Windows instead). I have redone the GParted/Frugal Installer process a few times to make sure it is not my user error, but I don't think it is.
(1) Does it sound plausible that my laptop (Dell Latitude 3190--quite new) cannot boot FossaPup if the USB has a "gpt" partition table? If not, what should I try to make that work?
(2) Is there anything I can do to sda3 on an "msdos" partition table to make it writeable in both FossaPup and Lubuntu? (Example: do I need to add a specific label or tag to sda3 in GParted?)
Thank you.