Week

1
Week 2Types of AS/400 Objects

• All AS/400 objects are categorized by object
  type. An objects type defines the objects
  purpose and how it can be used on the system.
• OS/400 provides more than 40 object types that
  encompass all applications and system resources,
  including programs, data, and hardware.

2
Week 2Types of AS/400 Objects (Continued)

• Object type Object description Attribute
  (subtype)
• CMD Command --
• FILE File PF -SRC (Source File)
• 
  PF -DTA (Physical file)
• LF (Logical file)
• DSPF (Display file)
• PRTF (Printer file)
• JOBD Job description --
• LIB Library --
• OUTQ Output queue --
• PGM Program (executable) Source language
• (e.g., CBL, CLP, RPG)
• QRYDFN Query definition --
• USRPRF User profile --

3
Week 2Types of AS/400 Objects (Continued)

• When you create an object and give it a name, the
  system assigns the object type, as determined by
  the command you used.
• Examples
• Command CRTUSRPRF (Create User Profile)
  generates the object type USRPRF
• Command CRTLIB (Create Library) generates the
  object type LIB

4
Week 2Types of AS/400 Objects (Continued)

• Some CL commands work with any type of object,
  but there are object types that have certain CL
  commands that can be used only for that type.
• Examples
• DSPOBJD (Display Object Description) command
  works for objects of any type
• DSPUSRPRF (Display User Profile) command works
  only for USRPRF objects

5
Week 2 Types of AS/400 Objects (Continued)

• When you create an object, it goes into a
  (User) library (unless the object created is, in
  fact, a library). This is not a physical
  collection of objects but a single-level
  directory to a group of related objects.

6
Week 2 Types of AS/400 Objects (Continued)

• A library also provides a logical reference to
  objects by using address pointers.
• The type and authorization level of each object
  is associated with the library entry for that
  object.
• (Present whiteboard illustration now)

7
Week 2 Requesting an Object

• When you request an object (by selecting a menu
  option or by entering a command), it usually is
  not necessary to specify the library name in
  which the object resides.
• You specify an object name (up to10-characters
  without a library reference), and the system
  searches the jobs current library list to locate
  an object matching the specified name and type
  appropriate for the request.

8
Week 2 Requesting an Object (Continued)

• Example You want to use the CALL command to
  execute a program. The CALL commands only
  required parameter is the name of the program so
  if you want to run a program named ACTCUS (to
  list all active accounts in a customer file), you
  would enter the command
• CALL ACTCUS

9
Week 2 Requesting an Object (Continued)

• The only valid object type for a CALL command is
  PGM, so if you include the object type in the
  library entry, the system can determine whether
  its type is appropriate for the requested
  operation without having to locate and load the
  actual object.

10
Week 2 Qualified/Unqualified Names

• To run, for example, program ACTCUS in library
  TSTLIB1, proceed in two ways
• Change the library list, or
• Use a qualified name for the object (the most
  direct because it includes a reference to a
  library the 10-character object name), which
  would take the form
• CALL libref/objname

11
Week 2 Qualified/Unqualified Names (Continued)

• In the form libref/objname, libref is an explicit
  library-object name therefore, to execute
  program ATCUS in library TSTLIB1, specify the
  following CALL command
• CALL TSTLIB1/ACTCUS
• Here, the system searches only library TSTLIB1
  for program ACTCUS.

12
Week 2 Qualified/Unqualified Names (Continued)

• The library specified in an explicit qualified
  name does not need to be in your library list,
  but you (the requester) must be authorized not
  only to use that library but also to use the
  object within the library. The first thing the
  system does is determine whether you have proper
  authority to the library you named.
• When you use a simple unqualified name, the
  search for an object is limited to your library
  list. The system determined that were authorized
  to use the library-list libraries when your job
  began. (Attempting to add to your library list a
  library to which you are not authorized will
  cause an error.)

13
Week 2 Qualified/Unqualified Names (Continued)

• If you are authorized to the library specified in
  an explicit qualified name but the system cannot
  find a matching object name of the appropriate
  type, or if you are not authorized to use the
  object, the system does not search beyond the
  specified library. Instead, the system returns a
  message such as Object OBJNAME in library
  LIBNAME not found or Not authorized to object
  OBJNAME in library LIBNAME.

14
Week 2 Qualified/Unqualified Names (Continued)

• It might be necessary to use a qualified name if
• Objects with the same name and type exist in more
  than one library in your library list
• You need an object that is not in any library in
  your library list
• To use a qualified name, you need authority
  adequate for the intended use, both to the object
  and library.