[Discuss] USB thumbdrive, Linux only usage: FAT vs NTFS vs other? TRIM support?

[tmetro+blu at gmail.com (Tom Metro)]

Matthew Gillen wrote:
> Create a single directory in the root of the thumb drive, and give that
> world-write and group-write, then give it set-group-ID bit ('chmod g+s
> dirname').
> 
> Every file created will inherit the group-id of the original directory...

How does that help if the numeric GIDs vary from machine to machine?

With FAT, NTFS, and several other file systems you can pass "-o
uid=value,gid=value" to 'mount' to force the appearance of ownership.

But a similar option doesn't exist for ext*. It is a recognized need,
and a patch was submitted in 2009:
http://lwn.net/Articles/343024/

but apparently not accepted.

The patch author says, "In an ideal world this would probably be
implemented as vfs feature rather than having it in every single file
system." Yes, perhaps as an option to the loop device, allowing you to
remount a file system while forcing the UID/GID.


Rich Pieri wrote:
> For Linux only I advise using ext2.

Likewise. And just live with needing to do the occasional "sudo chown -R
user /usbdrive" if UID/GIDs don't match the system.

I'd avoid NTFS if the primary use is on Linux. NTFS has file ownership
issues which can be even trickier to deal with when moving disks among
Windows machines.

FAT32 has a 4 GB file size limit (2 GB for FAT16), which can sometimes
be a problem.

 -Tom

-- 
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
Professional Profile: http://tmetro.venturelogic.com/