…you gotta manually compile the latest version of e2fsck.
WHY IS EVERYTHING SO DIFFICULT?!
OK, it’s not that difficult, but you would think the error messages for such a common operation would have been more helpful. I’m just trying to extend the Raspberry Pi image I just flashed so it takes up the whole SD card.
For the record, e2fsck is the ext-filesystem-specific component of the fsck filesystem utility. I have just this week been using it to check ext filesystems for errors like so:
e2fsck /dev/sdb5 (or whatever)
Make sure the drive is unmounted first:
umount /dev/sdb
Be careful; that’s umount, not unmount. I can’t tell you how many times that used to throw me off!
Update:
Additional issues! For some reason I could mount the filesystem once, but not again after that. Apparently I should have just resized the filesystem manually instead of using gparted to begin with. I resolved the issue thanks to the info found in this thread and the following commands:
(make sure partition is unmounted)
e2fsck -f /dev/sdX
resize2fs /dev/sdX