DEV-SAMPLES-C-PM-Simple

A Simple PM Window sample application for OS/2 Presentation Manager.

Description

This is a minimal OS/2 Presentation Manager (PM) application written in C. It demonstrates fundamental PM programming concepts by creating a standard frame window with a custom client area that accepts and displays keyboard input with automatic word-wrapping.

The program registers a custom window class (MyWindow) that allocates per-instance storage for a text buffer. Characters typed by the user are appended to the buffer and drawn in the client area using WinDrawText with word-break support. Pressing F3 exits the application.

Features

• Standard PM frame window with title bar, system menu, min/max buttons, and sizing border
• Custom window class registration with per-instance data storage
• Keyboard input handling — characters are accumulated and displayed
• Word-wrapped text rendering in the client area using GPI
• Window text protocol support (WM_SETWINDOWPARAMS / WM_QUERYWINDOWPARAMS)
• F3 key shortcut to exit

Requirements

• OS/2 Warp 4.5x or later (including ArcaOS)
• GCC 9.2 (bitwiseworks / kLIBC) or OpenWatcom 2.0 C compiler

Install build tools on ArcaOS:

yum install git gcc make libc-devel binutils watcom-wrc watcom-wlink-hll watcom-wipfc

Directory Structure

├── src/                    Source files
│   ├── simple.c           Main source file
│   ├── simple.h           Header file
│   ├── simple.def         Module definition file (BLDLEVEL)
│   ├── simple.ico         Application icon
│   └── simple-ow.lnk     OpenWatcom linker directives
├── bin-gcc/               GCC build output (created by build)
├── bin-ow/                OpenWatcom build output (created by build)
├── wiki/                  Screenshots
│   └── Simple_001.png     Application screenshot
├── compile-gcc.cmd        GCC build script
├── compile-ow.cmd         OpenWatcom build script
├── makefile-gcc            GCC makefile
├── makefile-ow             OpenWatcom makefile
├── .gitignore             Git ignore rules
├── LICENSE                BSD 3-Clause License
└── README.md              This file

Building

Using GCC

# Using the compile script
compile-gcc.cmd

# Using make directly
make -f makefile-gcc

Output: bin-gcc\simple.exe

Using OpenWatcom

# Using the compile script
compile-ow.cmd

# Using wmake directly
wmake -f makefile-ow

Output: bin-ow\simple.exe

Cleaning build artifacts

make -f makefile-gcc clean
wmake -f makefile-ow clean

BLDLEVEL Information

The executable includes BLDLEVEL information that can be queried using the OS/2 bldlevel command:

bldlevel simple.exe

Compile Notes

This version of this sample was modified to compile on ArcaOS with GCC 9 compiler.

1. Make sure you have the correct header files in your path. For GCC the correct ones are included in libc-devel, not the ones from the OS/2 Toolkit. Check your config.sys for SET INCLUDE=C:\usr\include.

2. Since the Watcom Resource Compiler (open source) and Watcom Linker are used instead of the classic rc.exe and ilink.exe, add to your config.sys:

   SET EMXOMFLD_LINKER=wl.exe
   SET EMXOMFLD_TYPE=WLINK
   SET EMXOMFLD_RC_TYPE=WRC
   SET EMXOMFLD_RC=wrc.exe
   

3. Run compile-gcc.cmd or make -f makefile-gcc to build. The compile script sets these environment variables automatically.

Version History

• 1.03 - 2026-07-24

  • Reorganised directory structure (source files in src/, build outputs in bin-gcc/ and bin-ow/)
  • Added OpenWatcom build support (makefile-ow, compile-ow.cmd, simple-ow.lnk)
  • Improved source code documentation
  • Improved README documentation
  • Added .gitignore

• 1.01 - 2023-07-16

  • Changed version to compile on GCC and to run on ArcaOS 5.0.7

• 1.0

  • Original version

License

BSD 3-Clause License — see LICENSE file for details.

Authors

• Martin Iturbide / OS2World (2023)
• Original Author

Links

• https://github.com/OS2World/DEV-SAMPLES-C-PM-Simple