link(1m)link(1m)NAME
link - A dcecp object that manages a soft link in CDS
SYNOPSIS
link create link_name_list {-to target_name [-timeout expiration_time
extension_time] | -attribute attribute_list}
link delete link_name_list
link help [operation | -verbose]
link modify link_name_list {[-add attribute_list] [-remove
attribute_list] [-change attribute_list]}
link operations
link show link_name_list [-schema]
ARGUMENTS
A list of one or more names of CDS soft links. The name of the link
operation for which to display help information.
DESCRIPTION
The link object represents a Cell Directory Service (CDS) soft link. A
soft link in CDS contains an attribute that has a name that is the same
as the name of the object the soft link points to. The soft link con‐
tains several built-in attributes, but users are free to add their own
attributes. Softlinks can point to objects, directories, and other
soft links.
ATTRIBUTES
The following CDS-defined attributes may be present in CDS link
objects: Specifies the creation timestamp (CTS) of the soft link. The
is a read-only DTS-style time stamp, which is set by the system. Spec‐
ifies the full name of the directory, object entry, or other soft link
to which the soft link points. Specifies a timeout value after which
the soft link is either renewed or deleted. Its value is a list of two
elements enclosed in braces, as follows: {expiration_time exten‐
sion_time} where: Is a date and time after which CDS checks for the
existence of the soft link's target and either extends or deletes the
soft link. The value is specified in the format yyyy-mm-dd-hh:mm:ss;
portions of it can be defaulted. Is a period of time by which to
extend the soft link's expiration time (if the server has validated
that the target still exists). The value is specified in the format
ddd-hh:mm:ss; portions of it can be defaulted. Specifies the timestamp
of the most recent update to an attribute of the soft link. The value
is a read-only DTS-style timestamp and is set by the system.
See the OSF DCE Administration Guide for more information about link
attributes.
OPERATIONS
link create
Creates a new soft link entry in CDS. The syntax is as follows: link
create link_name_list {-to target_name [-timeout expiration_time exten‐
sion_time] | -attribute attribute_list}
Options
Specifies a single name for the links to point to. If you do not use
this option, you must specify the link target with the -attribute
option. Specifies the expiration time and extension period for all
soft links named by the link_name_list argument. The option syntax is
as follows: {expiration_time extension_time} See ATTRIBUTES for more
detailed information about link timeouts. If you omit the -timeout
option, the link is permanent and must be explicitly deleted. Allows
you to specify attributes by using an attribute list. See ATTRIBUTES
for more detailed information about link attributes.
The create operation creates a new soft link entry in CDS. The
required link_name_list argument is a list of one or more full CDS
names of the soft links to be created. This operation returns an empty
string on success.
Privileges Required
You must have i (insert) permission to the directory in which you
intend to create the soft link.
Examples
The following command creates a soft link named /.:/sales/tokyo/price-
server that points to an object entry named /.:/sales/east/price-
server. The expiration value indicates that CDS checks that the desti‐
nation name /.:/sales/east/price-server still exists on June 25,1995,
at 12:00 p.m. If the destination name still exists, the soft link
remains in effect another 90 days. Thereafter, CDS will check that the
destination name exists every 90 days. dcecp> link create
/.:/sales/tokyo/price-server -to \ > /.:/sales/east/price-server -time‐
out {1995-06-25-12:00:00 90-00:00:00} dcecp>
You can enter the same information as above by using the -attributes
option, as follows: dcecp> link create /.:/sales/tokyo/price-server
-attribute { \ > {CDS_LinkTarget /.:/sales/east/price-server}
{CDS_LinkTimeout \ > {expiration 1995-06-25-12:00:00} {extension
90-00:00:00}}} dcecp>
link delete
Removes a link entry from CDS. The syntax is as follows: link delete
link_name_list
The delete operation removes a link entry from CDS. This task is usu‐
ally done through a client application. The required link_name_list
argument is a list of one or more full CDS names of the link entry to
be removed. This operation returns an empty string on success.
Privileges Required
You must have d (delete) permission to the link entry or A (Admin) per‐
mission to the directory that stores the link entry.
Examples dcecp> link delete /.:/sales/tokyo/price-server dcecp>
link help
Returns help information about the link object and its operations. The
syntax is as follows: link help [operation | -verbose]
Options
Displays information about the link object.
Used without an argument or option, the link help command returns brief
information about each link operation. The optional operation argument
is the name of an operation about which you want detailed information.
Alternatively, you can use the -verbose option for more detailed infor‐
mation about the link object itself.
Privileges Required
No special privileges are needed to use the link help command.
Examples
dcecp> link help create Creates the named link. delete
Deletes the named link. modify Adds, removes or changes
an attribute in the named link. show Returns the
attributes of a link. help Prints a summary of command-
line options. operations Returns a list of the valid opera‐
tions for this command. dcecp>
link modify
Changes attributes in the specified soft links. The syntax is as fol‐
lows: link modify link_name_list {[-add attribute_list] [-remove
attribute_list] [-change attribute_list]}
Options
Adds one or more new attributes to a soft link or adds values to exist‐
ing attributes when values are not already present. Add an attribute
type with no value by specifying an attribute type with no value.
Removes an entire attribute or some attribute values from a soft link.
If only the attribute type is specified after the option, the entire
attribute is removed. If an attribute type and value are specified,
only that value is removed. If an attribute or value is not present,
an error is returned. Changes one attribute value to another for a
soft link. Each attribute in the list has its existing value replaced
by the new value given in the attribute list. For multi-valued
attributes, all existing values are replaced by all the values listed
for the attribute in the attribute list. If an attribute or value is
not present, an error is returned.
The modify operation can be used to change two attributes of a soft
link: CDS_LinkTarget and CDS_LinkTimeout. The argument is a list of
names of soft links to be operated on. The operation takes the -add,
-remove, and -change options to specify an attribute list to describe
the changes. All the modifications are performed on each soft link
named in the argument. This operation returns an empty string on suc‐
cess.
Privileges Required
You must have w (write) permission to the link object.
Examples
The following example sets the link expiration time to
1998-01-20-12:00:00:00 and the extension time to 10 days: dcecp> link
modify /.:/depts/emergency -change { \ > {CDS_LinkTimeout {expiration
1998-01-20-12:00:00:00} {extension +10-0:0:0}}} dcecp>
link operations
Returns a list of the operations supported by the link object. The
syntax is as follows: link operations
The list of available operations is in alphabetical order except for
help and operations, which are listed last.
Privileges Required
No special privileges are needed to use the link operations command.
Examples
dcecp> link operations create delete modify show help operations dcecp>
link show
Returns attribute information associated with specified link entries.
The syntax is as follows: link show link_name_list [-schema]
Options
This option returns whether an attribute is single or multi-valued.
The type of value is specific to a link, meaning that the same
attribute can be single-valued on one link and multi-valued on another.
The show operation displays attribute information associated with spec‐
ified link entries. The required link_name_list argument is a list of
one or more full CDS names of the soft links you want to show. If more
than one link is shown, the attributes of all the soft links are con‐
catenated into one list. The order of the returned attributes is the
lexical order of the object identifiers (OIDs) of each attribute for
each object.
Privileges Required
You must have r (read) permission to the link entry.
Examples dcecp> link show /.:/depts/emergency {CDS_CTS
1994-07-11-17:47:59.755+00:00I0.000/00-00-c0-8a-df-56} {CDS_UTS
1994-07-11-17:52:44.698+00:00I0.000/00-00-c0-8a-df-56} {CDS_LinkTarget
/.../my_cell.acme_health.org/depts/radiology} {CDS_LinkTimeout
{expiration 1995-07-11-00:00:00.000}
{extension +10-10:00:00.000I-----}} dcecp>
dcecp> link show /.:/gumby -schema {CDS-CTS single} {CDS-UTS single}
{CDS-LinkTarget single} dcecp>
RELATED INFORMATION
Commands: dcecp(1m), dcecp_clearinghouse(1m), dcecp_directory(1m),
dcecp_object(1m).
link(1m)