odm_get_by_id Subroutine
Purpose
Retrieves an object from an ODM object class by its ID.
Library
Object Data Manager Library (libodm.a)
Syntax
#include <odmi.h>struct ClassName *odm_get_by_id( ClassSymbol, ObjectID, ReturnData)
CLASS_SYMBOL ClassSymbol;
int ObjectID;
struct ClassName *ReturnData;
CLASS_SYMBOL ClassSymbol;
int ObjectID;
struct ClassName *ReturnData;
Description
The odm_get_by_id subroutine retrieves an object from an object class. The object to be retrieved is specified by passing its ObjectID parameter from its corresponding ClassName structure.
Parameters
| Item | Description |
|---|---|
| ClassSymbol | Specifies a class symbol identifier of the form ClassName_CLASS, which is declared in the .h file created by the odmcreate command. |
| ObjectID | Specifies an identifier retrieved from the corresponding ClassName structure of the object class. |
| ReturnData | Specifies a pointer to an instance of the C language structure corresponding to the object class referenced by the ClassSymbol parameter. The structure is declared in the .h file created by the odmcreate command and has the same name as the object class. |
Return Values
Upon successful completion, a pointer to the ClassName structure containing the object is returned. If the odm_get_by_id subroutine is unsuccessful, a value of -1 is returned and the odmerrno variable is set to an error code.
Error Codes
Failure of the odm_get_by_id subroutine sets the odmerrno variable to one of the following error codes:
- ODMI_CLASS_DNE
- ODMI_CLASS_PERMS
- ODMI_INVALID_CLXN
- ODMI_INVALID_PATH
- ODMI_MAGICNO_ERR
- ODMI_MALLOC_ERR
- ODMI_NO_OBJECT
- ODMI_OPEN_ERR
- ODMI_PARAMS
- ODMI_TOOMANYCLASSES
See Object Data Manager (ODM) error codes for explanations of the ODM error codes.