Julian Elischer [1] and the Mach 2.5 Installation notes [2].
I was unable to pin point the exact version of Mach the fdisk utility appeared
as I didn't find documentation older than version 2.5 & no source code or repo
history. fdisk utility appears as a separate utility[3] in v2.5. Due to this,
I've avoided stating the exact version fdisk first appeared in Mach.
- Make correction pointed by textproc/igor
- Bump date
[1] https://groups.google.com/forum/#!searchin/comp.unix.bsd/14-Dec-89$20Robert$20Baron$20(rvb)$20at$20Carnegie-Mellon$20University%7Csort:relevance/comp.unix.bsd/Hhi45vAHxDg
[2] ftp://ftp.mcs.vuw.ac.nz/doc/misc/mach-i386-doc/i386_install.ps
[3] ftp://ftp.mcs.vuw.ac.nz/doc/misc/mach-i386-doc/i386_manpages.ps
e2di_size_high; even Linux ext2 filesystem code actually uses it
unconditionally this way and ext4 code finally also calls it that way
in their struct definition too; if there was any trace of this for other
purpose it's long gone
sysctl variable using ?= fails with EPERM, don't print an error
message.
Ideally setting a sysctl to the same value it already has should also
not fail regardless of permissions, but this would need to be done in
the kernel.
so they can't illegally reenter libc.
Fixes the problem Greg A. Woods describes in PR 51267, which might or
might not be the original submitter's problem.
The superblock field that distinguishes between 4.2BSD and 4.4BSD
inodes is really only relevant on a UFS1 file system. Make sure that
it is a UFS1 fs before using fs_old_inodefmt.
Note that the NetBSD newfs and mkfs utilities initialize fs_old_inodefmt
even for UFS2, so problems were apparent only on file systems created
by other operating systems, for example, FreeBSD.
distinct and allowing this makes certain useful tasks possible, such as
fixing an unpopulated /dev while a tmpfs is mounted over it.
However, require the paths to be different, as mounting a path directly over
itself has the side effect of causing any other mount points within that path
to no longer be accessible, and is difficult to unmount when done on /.
(e.g. umount_ffs, umount_nfs, etc.) exec it instead of calling
unmount(2).
Closes PR 698.
Note that the original plan for the PR also involved adding a generic
facility to store an alternate FS type name in the kernel to use when
unmounting. This was intended to support filesystems implemented as
loopback nfs servers, where the visible mount would be of type "nfs"
pointing at localhost; in that case one would want to be able to
provide an additional string in order to run an unmount program that
would both remove that mount and also shut down the loopback nfs
server daemon.
However, in the 21+ years since the PR was filed, loopback nfs servers
have gone out of favor (for good reasons) so I don't see any need to
worry about this case at present, especially since the PR has been
hanging around this long anyway. (If anyone still has a loopback nfs
server that they want to use a custom unmount program with, file a new
PR and assign it to me and I'll deal with it specifically in the nfs
mount args structure, which unmount already knows how to retrieve and
examine.)
It is my understanding that filesystems implemented with fuse (which
has displaced the loopback nfs server model) can already set the FS
type field so no further work is needed to allow them to use a custom
unmount program. If this is not the case, please let me know and I'll
attend to it.
There is no longer any need that I see to provide a general facility
for storing an alternate filesystem type name.
(One might also ask whether there's any real need for this
functionality at all any more; this is a fair question, but (a) the
change is small and (b) there are certainly cases when doing FS
research where you want a custom unmount program; been there & done
that.)
