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 M I [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) highly extendable  new environments System Licensed Internal Code (SLIC) [Knowledge about the hardware characteristics] Data Structure Object Internal details are hidden [encapsulation]

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)

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 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 Library Create

Naming of Commands Typically start with the following verbs: CL VerbEnglishDescription CALLCallExecutes a program GOGo toExecutes a Menu CPYCopyCopies a file CRTCreateCreates an object DSPDisplayDisplays something about an object WRKWorks WithWorks with an object

CL Commands Some typical nouns CL NounEnglishDescription LIBLibraryObject that holds Objects LIBLLibrary ListList of Libraries for a Job OUTQOutput QueueObject that stores Spool Files JOBQJob QueueObject that stores Batch Jobs to be processed FDFile DescDescription of file FFileObject that stores data USRPRFUser ProfileObject 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 MenuDescription MAINMain Menu PROGRAMProgrammers Menu MAJORSorts Commands CMDCPYCopy Commands CMDDSPDisplay Commands CMDWRKWork With Commands CMDLIBLibrary Commands CMDMSGMessage Commands CMDOUTQOutput Queue Commands CMDUSRPRFUser 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