Transcript iSeries architecture

iSeries
Lecture 2
Technology independence
• Technology independence  change the underlying hardware
architecture and add new functionality without disrupting customers.
• Other manufacturers found ways to incorporate new functions and
new hardware designs. Difference  existing application programs
cannot use these new capabilities.
• Intel [1985]  added 32-bit extensions to the original 16-bit
architecture.
– Any 16-bit application could still run on the new 32-bit chips, but it ran in a
16-bit mode that did not use any of the 32-bit extensions.
• Intel [1997] made a significant change to the architecture when it
added the multimedia extension (MMX).
– Older applications could run on the new chips but just couldn't use MMX.
• PC industry  acceptable to require applications to be rewritten to
use the newest hardware functionality
iSeries architecture
Application programs and OS/400 programs
MI
[a logical, not a physical, interface to the system]
•MI architecture has two components
– a set of instructions and the operands upon which those instructions act
•bit and byte operands + data structures [Objects]
•application program interfaces (APIs)
Internal details
are hidden
Data
Structure
[encapsulation]
Object
•highly extendable  new environments
System Licensed Internal Code (SLIC) [Knowledge about the hardware characteristics]
Conventional Machine Interface
iSeries MI
Note: There is no
memory at the MI
The System Licensed Internal Code [Kernel]
• The iSeries' operating system  OS/400 [MI] + SLIC
Operating System Functional Split
System-wide security is in OS/400,
while the authorization to system
resources is in the SLIC
Technology-Independent Machine Interface
Objects
• how the iSeries uses objects .
• iSeries is an object-based system [no inheritance]
• This permits only iSeries servers to make technology advances in
the hardware, such as storage, memory, and processor technology,
while protecting end-users' investments in existing applications
OBJECTS
• LIBRARY -> MOHAMED
• OBJECT -> QRPGSRC (Source File
holds all RPG programs)
• MEMBERS -> SALESPGM (Single
program source)
• RECORDS -> Single line of code in
program
Continued ...
• LIBRARY/OBJECT (*object type)
• ALLOWED
– MOHAMED/PAYROLL (*File)
– MOHAMED/PAYROLL (*Pgm)
• NOT ALLOWED
– MOHAMED/PAYROLL (*File)
– MOHAMED/PAYROLL (*File)
Different types of Screens
• Menu
– System Menus (GO XXXXX)
– Utility Menus (STRXXX)
– User Defined Menus
• List (member type *all)
• Command Entry (option 3 in PDM)
• Information (help)
Prompting
• Command prompting
• Field prompting
Menu
• Menus
GO MAIN
main menu (F16)
GO MAJOR
major commands menu (F4)
GO VERB
action menu
GO SUBJECT
objects menu
GO CMDxxxx
verb, noun, function
Menu Questions
• Which menu groups together all of the
Work With commands?
• Which menu groups together all of the
commands by subject?
User Profile
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•
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Same name as your User ID
Stores your password
Points to your Current Library
Points to your default output queue
Runs your startup programs and menus
Points to the object that stores your default
library list
• Lets you know the last time your signed on
CL Syntax
Command-name
(space) parameter
Commands that do not Require the
Entry of Parameters
• WRKJOB
• WRKACTJOB
• WRKSBMJOB
Keyword vs Positional Notation
Keyword
WRKOUTQ OUTQ(PRT01)
CRTLIB LIB(MOHAMED) +
TEXT(‘Mohameds Library’)
Positional
WRKOUTQ PRT01
CRTLIB MOHAMED *TEST ‘Mohameds
Library’
Naming of Commands
• Based on English!
• Combination of Verb and Noun
CRTLIB
Create
Library
Naming of Commands
• Typically start with the following verbs:
CL Verb English Description
CALL
GO
CPY
CRT
DSP
WRK
Call
Go to
Copy
Create
Display
Executes a program
Executes a Menu
Copies a file
Creates an object
Displays something about an
object
Works With Works with an object
CL Commands
• Some typical nouns
CL Noun English Description
LIB
LIBL
OUTQ
JOBQ
Library
Library List
Output Queue
Job Queue
FD
F
USRPRF
File Desc
File
User Profile
Object that holds Objects
List of Libraries for a Job
Object that stores Spool Files
Object that stores Batch Jobs to
be processed
Description of file
Object that stores data
Object that lists attributes about
a Sign On Id
CL Commands cont’d
• How do I find the exact syntax (including
keywords) of a command?
Answer:Use AS400 Menus
Use AS400 Prompts (F4)
by pressing F4 at a Command line
by typing command and pressing F4
CL Commands
• AS400 Menus
Menu
Description
MAIN
PROGRAM
MAJOR
CMDCPY
CMDDSP
CMDWRK
CMDLIB
CMDMSG
CMDOUTQ
CMDUSRPRF
Main Menu
Programmers Menu
Sorts Commands
Copy Commands
Display Commands
Work With Commands
Library Commands
Message Commands
Output Queue Commands
User Profile Commands
How do I find the Keywords to a
command?
• Type the command and press F11
Library Lists
• Each job has an attached Library List
• Different Types of Libraries:
– System:
IBM Supplied
– Product:
Added automatically when an IBM
product is used
– Current:
Defined by an individual user ID
User ID’s default Library
– User:
Non-IBM Supplied Libraries
Created by Business to organize programs,
files, etc.
Library List
• Determine where a Job finds Objects