Date Published: October 1, 2024
In IBM i environments, interacting with the Integrated File System (IFS) can sometimes be cumbersome due to its Unix-like structure and command set. This is where a custom RPGLE tool, like the one described here, becomes invaluable. It simplifies IFS operations such as file creation, writing, and permission management, making these tasks easier and more intuitive for RPGLE developers.
However, I must mention that I am a bit hesitant to publish this IFS tool since the SQL version (QSYS2.IFS_WRITE) is already available starting from IBM i 7.3 TR12. The tool I’ve created came before IFS_WRITE was made available. That being said, here is the tool, and it should be easy to use. Just follow the example in the use case section.
How the Tool Works
The tool comprises two main components:
1. File Creation: The ifs_Create_File procedure handles file creation, managing permissions and code page configurations. It returns a file handle that uniquely identifies the file in subsequent operations.
2. File Writing: The ifs_Write_File procedure facilitates data writing. It handles nuances such as delimiters (for CSV files), removing trailing tab characters, and optionally writing newline characters.
Together, these procedures enable developers to easily create and manipulate files in the IFS.
Use Case: Writing Text and CSV Files
The practical example demonstrates how this tool can be used to write both text and CSV files to the IFS.
- Text File Writing: The tool creates a simple text file (Test.txt) and writes two lines of text. This process is straightforward and showcases how easily unstructured data can be written to the IFS using RPGLE.
- CSV File Writing: CSV files are slightly more structured, requiring delimiters to separate data fields. The tool handles this seamlessly, allowing the user to focus on data formatting rather than file system management.
In both cases, the ifs_FileClose procedure ensures that file handles are closed properly, freeing up system resources.
Why Use This Tool?
This IFS tool offers several advantages:
- Simplicity: By abstracting the low-level details of IFS interaction, the tool simplifies file handling for RPGLE developers.
- Flexibility: It supports both text and structured file types like CSV, making it versatile for various use cases.
- Efficiency: The tool is designed for performance, managing file permissions and code pages efficiently, ensuring that files are correctly formatted for both iSeries and external systems.
While IBM i 7.3 TR12 introduces SQL-based alternatives such as QSYS2.IFS_WRITE, this tool still serves as a valuable option for developers looking for a pure RPGLE-based solution, especially in environments where upgrading to newer IBM i versions is not yet feasible.
Conclusion
The RPGLE IFS tool is a robust utility that makes file management in the IFS easier and more accessible. With minimal code, it provides the ability to create, write to, and manage files—whether simple text files or structured CSVs. This tool is essential for any RPGLE developer working with the IFS on IBM i, especially if SQL-based solutions aren't an option.
Even though the SQL alternative is available, the tool presented here remains simple, powerful, and easy to use for those accustomed to RPGLE. Just follow the examples provided in the use case section, and you’ll be ready to integrate it into your own projects.
#RPGLE #IBM #IBMi #FileManagement #SoftwareDevelopment #TechInnovation 🚀💻
How to Use the JSIFSTOOL Service Program
1. Source Code Placement
Ensure the following setup:
- The source code QPROTOSRC/JSIFSTOOL must be placed in the QPROTOSRC source member.
- The source code QRPGLESRC/JSIFSTOOL must be placed in the QRPGLESRC source member.
- Both source members should reside within the same library.
2. Purpose
The QPROTOSRC/JSIFSTOOL member is used within QRPGLESRC to copy the necessary
declarations and parameters for the application to function as a service program. This is achieved by binding
the /copy directive during the compilation process.
Additionally, the QPROTOSRC/JSIFSTOOL source code is utilized by RPG applications that require
this service program.
3. Compilation Instructions
Step 1: Create the Module
CRTRPGMOD MODULE(*CURLIB/JSIFSTOOL) SRCFILE(*CURLIB/QRPGLESRC) SRCMBR(JSIFSTOOL) DBGVIEW(*SOURCE) REPLACE(*YES)
Step 2: Create the Service Program
CRTSRVPGM SRVPGM(*CURLIB/JSIFSTOOL) EXPORT(*ALL) ACTGRP(*CALLER)
Note: The *CURLIB is used as the default library in this example. You may specify any
library where you want the objects to be stored.
4. Binding Directory
Once the service program is created, it should be added to a binding directory. For example, I use JASTOOL as my binding directory. You can use any binding directory that suits your needs.
ADDBNDDIRE BNDDIR(*CURLIB/JASTOOL) OBJ((JSIFSTOOL))
Use Case
To use the IFS function tool see below example: