Consistently show or hide RAM FS

[humdinger]

This is R1/beta4, 64bit.

"RAM FS" is new in beta4. AFAIK - please elaborate if there's more to it - it's a ram disk that is used by some ported software to eek out performance by storing temporary files in memory.

I suppose a user could also use "RAM FS" when being aware of its evanescent quality.

If so, "RAM FS" should fit in consistently with 'normal disks', otherwise it should be hidden from the user. Current inconsistencies I found:

• It appears in a Tracker drill-down-navigation together with all other mounted disks, but not on the Desktop (or the Disks window).
• You can't navigate to it in a file dialog.
• It does not appear mounted as "/RAM FS" in Terminal.
• It does not appear mounted as "RAM FS" in Tracker's Mount menu.
• It's not shown in DriveSetup or Installer, but I suppose it wouldn't make sense there...
• DiskUsage always reports 0 bytes (does it size dynamically, or is it supposed be fixed sized?)

I suppose, if "RAM FS" isn't intended for end-users, we'd just have to fix the first item: remove it from Trackers drill-down-navigation.

[X512]

By default ramfs is mounted to /boot/system/var/shared_memory to implement POSIX shared memory API (​shm_open etc.). But ramfs can be also used as RAM disk for storing regular files in memory that may be useful for regular users (but there are no user-friendly interface for now).

[waddlesplash]

Removing it from drill-down navigation sounds best, yes.

[bipolar]

I'm seeing related "inconsistencies"/issues regarding the "config" and "system" packagefs mounts (they appear next to "RAM FS" from the right-click menu on the Disks icon, or when drilling down from Desktop).

All three of them also show an "Unmount" item from their context menues. You get a warning (about it being busy) when attempting to unmount "system" from a "/boot/" Tracker view, but it lets you do it.

System still seems to work OK afterwards (other than all of them having disappeared from the Disks context menu and Desktop's drill-down), and now right clicking on /boot/system shows the same menu as for any other folder.

All a bit puzzling from and end user point of view :-D

Annnd... spoke too soon... "everything but Tracker" (or so it seems) breaks till you reboot :-D (bash can't find any command, Leaf menu appears empty, etc).

Maybe there should be extra-protections/handling/hiding in Tracker for all three "RAM FS" (the one for shared_memory at least), "config" and "system" as they are "special mounts"?

[waddlesplash]

Fixed by removing the PERSISTENT flag in hrev57238, which seemed to work fine and did not cause any major issues that I could see.