• The Four Hundred
  • Subscribe
  • Media Kit
  • Contributors
  • About Us
  • Contact
Menu
  • The Four Hundred
  • Subscribe
  • Media Kit
  • Contributors
  • About Us
  • Contact
  • File Members and the Library List

    May 25, 2005 Dominic Lefevre

    What happens when an RPG or COBOL program opens a file? For one thing, the system has to find the file. And where does it look for the file? Everyone knows the answer to that question. The system searches the libraries in the library list, beginning with the system library list, proceeding through the product libraries, the current library, and finally the user libraries. The system selects the first file it finds of the desired name, right? Not necessarily.

    The exception comes when the system is searching for a certain file member. If the system does not find the desired file member in a file of the desired name, the system will continue to search the libraries in the library list.

    Here’s a little test you can run for yourself. Create two files of the same name in different libraries. I suggest you use work libraries. You can use QTEMP for one of them. Give the members different names.

    crtpf qtemp/x rcdlen(48) mbr(one) 
    crtpf mylib/x rcdlen(48) mbr(two)
    

    Use a database utility, such as DFU, to load one record into each of the files. I suggest you key ONE in member ONE and TWO in member TWO.

    Use the Display Physical File Member (DSPPFM) command to display the files.

    dsppfm x one
    dsppfm x two
    

    You will see that the system will find the right member, no matter the order of the libraries in the library list.

    Source physical files also work well for this test. Give it a try with files of the same name, such as QRPGSRC, in different libraries.

    This same behavior holds true with RPG (and, I assume, COBOL) programs. RPG normally opens the first member of a file, but if you override a file to a certain member, or you add the EXTFILE and EXTMBR keywords in RPG F specs, the system will continue to scan through the libraries in the library list until it finds a file member of the proper name.


    The system is not consistent, however. The Run Query command chokes if it does not find the desired member in the first instance of the desired file.

    runqry qry(*none) qryfile((x two))  
    runqry qry(*none) qryfile((x one))  
    

    One of the two commands generates message QRY1612 (Member ONE not in file X in MYLIB).

    Share this:

    • Reddit
    • Facebook
    • LinkedIn
    • Twitter
    • Email

    Tags:

    Sponsored by
    PERFSCAN

    Revolutionary Performance Management Software

    At Greymine, we recognize there is a void in the IT world for a dedicated performance management company and also for a performance management tool that’s modern, easy to use, and doesn’t cost an arm and a leg. That’s why we created PERFSCAN.

    PERFSCAN is designed to make your job easier. With revolutionary technology, an easy-to-read report and graphics engine, and real time monitoring, tasks that used to take days can now take minutes. This means you will know your system better and will be able to provide better service to your customers.

    OUR FEATURES

    PERFSCAN is full of robust features that don’t require you to take a three-day class in order to use the product effectively.

    Customizable Performance Reporting

    Whether you are troubleshooting a major system problem or simply creating a monthly report, PERFSCAN lets you select any combination of desired performance metrics (CPU, Disk, and Memory).

    User Defined Performance Guidelines

    No matter if you are a managed service provider managing complex systems in the cloud or a customer analyzing your on-premises solution, PERFSCAN gives you the flexibility to define all mission critical guidelines how they need to be.

    Understanding The Impact Of Change

    Tired of all the finger pointing when performance is suffering? PERFSCAN’s innovative What’s Changed and Period vs. Period analysis creates a culture of proof by correlating known environmental changes with system performance metrics.

    Comprehensive Executive Summary

    Creating performance graphs is easy. Understanding what they mean is another thing. With one mouse click, PERFSCAN includes an easy-to-understand executive summary for each core metric analyzed.

    Combined Real-Time Monitor And Performance Analysis Tool

    With PERFSCAN’s combined built in enterprise real-time monitor and historical performance analysis capability, you will always know how your mission-critical systems are performing.

    Cloud Performance Reporting Is Easy

    Managing performance for production systems in the cloud can be a black hole to many system administrators. The good news is PERFSCAN analyzes all core metrics regardless of the location. That’s why MSPs and customers love PERFSCAN.

    Detailed Job Analysis

    PERFSCAN shows detailed top job analysis for any desired period. All metrics are displayed in two ways: Traditional Report and Percentage Breakdown Pie Chart. This toggle capability instantly shows the jobs using the most system resources.

    Save Report Capability

    Your boss lost the report you gave to him on Friday. Now what do you do? With PERFSCAN’s save report capability, any report can be retrieved in a matter of seconds.

    Professional PDF Reporting With Branding

    Creating professional looking reports for your customers has never been easier with PERFSCAN. Branding for our partners and service provider customers is easy with PERFSCAN.

    Check it out at perfscan.com

    Share this:

    • Reddit
    • Facebook
    • LinkedIn
    • Twitter
    • Email

    WRQ Improves Security of Terminal Emulation Suite Intel Partnership Doesn’t Hurt iSeries Strategy, JDA Software Says

    Leave a Reply Cancel reply

Volume 5, Number 21 -- May 25, 2005
THIS ISSUE
SPONSORED BY:

ProData Computer Svcs
iTera
WorksRight Software

Table of Contents

  • Creating Pivot Tables on the iSeries
  • File Members and the Library List
  • Admin Alert: Configuring Windows Desktops to Use SSO

Content archive

  • The Four Hundred
  • Four Hundred Stuff
  • Four Hundred Guru

Recent Posts

  • Fortra Issues 20th State of IBM i Security Report
  • FNTS Launches Managed Services for Power Servers in IBM Cloud
  • Total LTO Shipped Capacity Up Slightly in 2022
  • Four Hundred Monitor, May 24
  • Update On Critical Security Vulnerability In PowerVM
  • Critical Security Vulnerability In PowerVM Hypervisor
  • IBM Power: Hosted On-Premises Or In The Cloud?
  • Guru: Watch Out For This Pitfall When Working With Integer Columns
  • As I See It: Bob-the-Bot
  • IBM i PTF Guide, Volume 25, Number 21

Subscribe

To get news from IT Jungle sent to your inbox every week, subscribe to our newsletter.

Pages

  • About Us
  • Contact
  • Contributors
  • Four Hundred Monitor
  • IBM i PTF Guide
  • Media Kit
  • Subscribe

Search

Copyright © 2023 IT Jungle