2009/4/10 <per...@pluto.rain.com>: > Polytropon <free...@edvax.de> wrote: >> On Thu, 09 Apr 2009 12:47:23 -0700, per...@pluto.rain.com wrote: >> > It's an SD card, not a "drive", so I had not expected it to be >> > partitioned; but yes, it is: >> > >> > $ ls -l /dev/da0* >> > crw-r----- 1 root operator 0, 244 Feb 14 15:09 /dev/da0 >> > crw-r----- 1 root operator 0, 245 Feb 14 15:09 /dev/da0s1 >> >> Why don't you expect this? As far as I know, if something is >> msdosfs-formatted (read: any "Windows" readable file system, >> FAT), it always involves a "slice device". I never found a >> situation where access to /dev/da0 would work. > > My experience is exactly the reverse. I've never before seen a > removable-media device (floppy, Zip-drive, JAZ drive) that *did* > have a DOS "partition" table aka BSD "slice" table. Surely you > would not expect a USB floppy to show up as /dev/da0s1? > > AFAIK the reason for creating slices is to identify sections of > the device for use by different OS -- something often needed > for multi-boot from a hard drive but seldom on removable media. > I sure wasn't planning to use part of this SD card for my camera > to store pictures on, and the rest for FreeBSD backups :)
Aha, careful. A flash drive/card is more like a removable hard drive. Since it's so much bigger than a floppy etc (typically) it makes sense to have a proper slice (partition) structure. If you want to boot off a floppy, it's a different operation from booting off a HDD for precisely this reason. Whereas a floppy isn't a proper, 'fixed' type disk; it's a tiny thing, suitable for max ~10 files. There's no need to have the overhead of a partition table, MBR etc. Same with CDs, booting off them involves several strange fudges (El Torito). Since a flash card would be a sensible thing to boot off, the designers want it to look more like a hard drive; as well as having the flexibility. Chris -- A: Because it messes up the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail? _______________________________________________ freebsd-questions@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "freebsd-questions-unsubscr...@freebsd.org"
