Introduction

If you are a Windows user stepping into the world of IBM i, you might feel a bit lost. Unlike Windows, which has folders, files, and executables, IBM i follows a unique object-based architecture that works differently. But don’t worry! This blog will help you map IBM i concepts to familiar Windows features, making it easier to understand.

Let’s take a look at some IBM i basics and how they compare to Windows.

1. Libraries vs. Directories

Windows:

In Windows, you store files inside folders (directories), and you can create subfolders inside them to organize your files.

IBM i:

In IBM i, instead of folders, we have libraries. A library is a container that holds different objects like programs, tables (files), and indexes. However, unlike Windows directories, libraries cannot have sub-libraries—everything stays at the same level.

Example:

• A Windows folder like C:\Projects\SalesData might contain Excel files.
• On IBM i, you would have a library SALESDATA that contains different objects, such as reports, programs, or database tables.

Think of a library as a Windows directory that holds all types of files, but you can’t nest it inside another library.

2. Files vs. Objects

Windows:

Windows has different file types like .txt, .docx, .exe, etc.

IBM i:

IBM i doesn’t just have files - it has objects. Everything on IBM i is an object, whether it's a file, a program, a user profile, or a job.

Example:

• In Windows, a .txt file contains text.
• In IBM i, a physical file (PF) stores data, similar to a database table.
• A program object (PGM) in IBM i is like an .exe file in Windows - it runs instructions.

Think of IBM i as a system where every item (file, program, database table) is a different type of object, instead of just being a file.

3. Running Programs: Executables vs. Jobs

Windows:

On Windows, you run applications (like notepad.exe), and they start a process.

IBM i:

In IBM i, processes are called jobs. A job is a running instance of a program.

• Interactive jobs run when you log in (similar to opening an application in Windows).
• Batch jobs run in the background without user interaction (like a scheduled task in Windows Task Scheduler).

Example:

• Opening Excel.exe in Windows starts a new process.
• Running CALL MYPGM in IBM i starts a job that runs the MYPGM program.

Think of IBM i jobs like Windows processes. Interactive jobs are like programs you open manually, and batch jobs are like scheduled tasks.

4. Security: User Permissions and Authorities

Windows:

In Windows, you have users, groups, and file permissions. You can give users Read, Write, or Execute permissions on files and folders.

IBM i:

IBM i has a similar system but uses authority levels:

• User profiles control access.
• Object authorities define who can read, write, or execute an object.

Example:

• In Windows, you might allow John to read C:\Reports, but not modify it.
• In IBM i, you can grant USER1 read-only access to the REPORTS library but prevent changes.

Think of IBM i security like Windows file permissions, but applied to all system objects, not just files.

5. Message Handling: Notifications vs. Message Queues

Windows:

Windows uses pop-up notifications and system logs for errors and alerts.

IBM i:

IBM i uses message queues. Messages are stored in queues and can be reviewed later.

• The QSYSOPR message queue is like Windows Event Viewer—it logs system messages.
• Users have personal message queues, like Windows notifications.

Example:

• A Windows error might appear as a pop-up saying, “Low disk space.”
• In IBM i, a similar system message would be sent to the QSYSOPR message queue.

Think of IBM i message queues as a mailbox where system messages are delivered instead of pop-up notifications.

6. Scheduling Tasks: Task Scheduler vs. Job Scheduler

Windows:

Windows Task Scheduler lets you schedule programs to run at specific times.

IBM i:

IBM i has a built-in Job Scheduler (WRKJOBSCDE) that schedules jobs.

Example:

• In Windows, you schedule a backup script using Task Scheduler.
• In IBM i, you schedule a CL program (SAVLIB) using WRKJOBSCDE.

IBM i’s Job Scheduler works like Windows Task Scheduler but is more deeply integrated into system operations.

Conclusion

If you're coming from Windows, IBM i might feel different at first. But by mapping IBM i concepts to familiar Windows features, it becomes easier to understand:

• Libraries are like directories, but without subfolders.
• Files are objects, and everything (programs, users, jobs) is treated as an object.
• Jobs are like Windows processes, running programs interactively or in the background.
• Security is based on user profiles and object authorities, similar to Windows file permissions.
• Message queues are like system notifications and logs.
• The Job Scheduler automates tasks like Windows Task Scheduler.

By understanding these mappings, transitioning from Windows to IBM i becomes much smoother.