NAME
cdnode — format of a CDFS cdnode
SYNOPSIS
#include <sys/types.h>
#include <sys/cdnode.h>
DESCRIPTION
This entry describes the cdnode structure and related concepts for the
CDFS
file system.
The
CDFS
file system does not have the concept of
a separate entity called an inode.
The information normally found in an
HFS
inode is kept in a
cdnode
data structure.
However, the cdnode data structure
does not reside on the physical media,
but instead is kept in kernel memory space only.
The cdnode information is used to uniquely identify a file.
The information kept in the cdnode structure is obtained
from two other data structures in the
CDFS
file system:
- 1.
Directory record for the file or directory, and
- 2.
Extended attribute record
(XAR)
for the file or directory, if one exists.
Because few files usually have
XARs associated with them,
the cdnode information most often consists
only of attributes given by the directory record for the file.
Since cdnodes are kept in kernel memory,
they cannot be directly accessed by the user.
The
stat()
system call attempts to map whatever information
is included in the cdnode for a given file
into the standard stat structure (see
stat(2)).
However, since a cdnode includes information
that does not have corresponding fields in the stat structure,
that information cannot be mapped and therefore cannot be accessed.
No method is provided to access an entire cdnode structure.
FILES
/usr/include/sys/cdnode.h
/usr/include/sys/cdfsdir.h
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