Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cwjcc!gatech!hubcap!ncrcae!ncrlnk!uunet!auspex!guy
From: guy@auspex.UUCP (Guy Harris)
Newsgroups: comp.unix.questions
Subject: Re: Out of gnodes, solution found.
Message-ID: <1048@auspex.UUCP>
Date: 18 Feb 89 19:36:11 GMT
References: <18404@adm.BRL.MIL>
Reply-To: guy@auspex.UUCP (Guy Harris)
Organization: Auspex Systems, Santa Clara
Lines: 20


 >As Ross explained:
 >
 >> FYI, gnodes are an in-core abstraction of the inode. They are used to
 >> reference files in both normally mounted file systems and NFS mounted
 >> file systems. 4.3 BSD has the same idea, but they're called 'vnodes'.

His explanation is correct, except that he claims that 4.3BSD has
vnodes.  It doesn't.  SunOS has vnodes, as do systems that have picked
up the vnode code from Sun's ONC/NFS source releases.

Vnodes aren't limited to "normally mounted file systems" (by which I
presume you mean UNIX-style file systems on local disks) and NFS mounted
file systems, and I think gnodes aren't, either.  They're both intended
as general mechanisms to support various types of OS objects that behave
like file systems and like files/directories on file systems; they can
support multiple kinds of local file systems (V7/S5, 4.2BSD, MS-DOS,
Files-11, etc.), multiple kinds of remote file systems (NFS, AT&T's RFS,
etc.), and multiple kinds of weird file systems ("/proc", which gives
you a view of the system process table and the systems processes; etc.).