Red Hat GLOBAL FILE SYSTEM 4.6, Manual

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13. Context-Dependent Path Names
Context-Dependent Path Names (CDPNs) allow symbolic links to be created that point to
variable destination files or directories. The variables are resolved to real files or directories
each time an application follows the link. The resolved value of the link depends on the node or
user following the link.
CDPN variables can be used in any path name, not just with symbolic links. However, the
CDPN variable name cannot be combined with other characters to form an actual directory or
file name. The CDPN variable must be used alone as one segment of a complete path.
Usage
For a Normal Symbolic Link
ln -s TargetLinkName
Target
Specifies an existing file or directory on a file system.
LinkName
Specifies a name to represent the real file or directory on the other end of the link.
For a Variable Symbolic Link
ln -s VariableLinkName
Variable
Specifies a special reserved name from a list of values (refer to Table 4.5, “CDPN
Variable
Values” ) to represent one of multiple existing files or directories. This string is not the name
of an actual file or directory itself. (The real files or directories must be created in a separate
step using names that correlate with the type of variable used.)
LinkName
Specifies a name that will be seen and used by applications and will be followed to get to
one of the multiple real files or directories. When
LinkName
is followed, the destination
depends on the type of variable and the node or user doing the following.
Variable Description
@hostname
This variable resolves to a real file or directory named with the
hostname string produced by the output of the following command:
echo `uname -n`
Usage
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