[ Bottom of Page | Previous Page | Next Page | Contents | Index | Library Home |
Legal |
Search ]
Technical Reference: Base Operating System and Extensions, Volume 2
wlm_read_classes Subroutine
Purpose
Reads the characteristics of superclasses or subclasses.
Library
Workload Manager Library (libwlm.a)
Syntax
#include <sys/wlm.h>
int wlm_read_classes (wlmargs, class_tbl, nclass)
struct wlm_args *wlmargs;
struct class_definition *class_tbl;
int *nclass;
Description
The wlm_read_classes subroutine is used to get the
characteristics of the superclasses or the subclasses of a given subclass
of a Workload Manager (WLM) configuration.
- If the name of a configuration is passed in the confdir field, the wlm_read_classes subroutine
reads the property files of the classes of the specified configuration. If confdir is set to a null string ('\0'), wlm_read classes reads the classes' characteristics from the in-core
WLM data structures when WLM is on (and returns an error when WLM is off).
Note
These values may be different from the values in the property
files of the configuration pointed to by /etc/wlm/current. For instance when a WLM administrator has modified the property files
for the configuration pointed to by /etc/wlm/current but
has not refreshed WLM yet. Another example is if applications dynamically
created or modified classes through the API without saving the changes in
the current configuration property files.
If your application specifically needs to access the properties
of the classes as described in the /etc/wlm/current configuration,
you must specify current as the configuration name
in confdir.
If the name of a set of time-based
configurations is passed in the confdir field, the wlm_read_classes subroutine reads the classes of the currently
applicable configuration of the set.
- If the name of a valid superclass of the given configuration is passed
in the name field of the class_descr substructure of wlmargs, wlm_read_classes reads the property files for the subclasses of this superclass. If a
null string ('\0') is passed in the name field, wlm_read_classes reads the property files for the superclasses
of the WLM configuration described above.
- When wlm_read_classes is successful, the characteristics
of the superclasses or subclasses are copied into the array of class_definition structures pointed to by class_tbl. The integer value pointed to by nclass indicates
the maximum number of class definitions to be copied. Upon successful return
from the function, this value reflects the actual number of classes read.
If the number of elements copied by wlm_read_classes is
strictly smaller than the number of elements passed as an argument, all the
classes have been read. If it is equal, it may mean that some classes were
not copied into the class_tbl array because its size
is too small.
The maximum number of classes read by wlm_read_classes is 67 (64 user-defined superclasses plus System, Shared
and Default) when reading superclasses and 63 (61 user-defined subclasses
plus Shared and Default) when reading subclasses characteristics.
- Upon successful return from wlm_read_classes, the
substructure class of type struct class_definition of the structure pointed to by wlmargs contains
the default values of various class attributes for the returned set of classes.
This operation does not require any special privileges and is accessible
to all users.
Parameter
wlmargs |
Specifies the address of a struct wlm_args data
structure.
The following fields of the wlm_args structure
and the embedded substructures need to be provided:
- versflags
- Needs to be initialized with WLM_VERSION.
- confdir
- Specifies the name of a WLM configuration. It must be either the name
of a valid subdirectory of /etc/wlm or a null string
(starting with '\0').
- name
- Specifies the name of a superclass existing in the specified configuration
or a null string.
All the other fields can be left uninitialized. |
class_tbl |
Specifies the address of an array of structures of type struct class_definition. Upon successful return from wlm_read_classes, this array contains the characteristics of the classes
read. |
nclass |
Specifies the address of an integer containing the maximum number of
element (class definitions) for wlm_read_classes to
copy into the array above. If the call to wlm_read_classes is successful, this integer contains the number of elements actually
copied. |
Return Values
Upon successful completion, the wlm_read_classes subroutine
returns a value of 0. If the wlm_read_classes subroutine
is unsuccessful, a nonzero value is returned.
Error Codes
For a list of the possible error codes returned by the WLM API functions,
see the description of the wlm.h header file.
Related Information
The lsclass command.
The wlm.h header file.
[ Top of Page | Previous Page | Next Page | Contents | Index | Library Home |
Legal |
Search ]