Object Windows Library
| Company type | Software framework |
|---|---|
| Industry | Software development |
| Founded | 1991 |
| Founder | Borland Software Corporation |
| Defunct | 1997 |
| Fate | Replaced by Visual Component Library (VCL) |
| Successor | Visual Component Library (VCL) |
Area served | Windows, selected OS/2 platforms |
Key people | Yura Bidus (OWLNext project leader) |
| Products | C++ application framework |
| Owner | Borland Software Corporation (original), OWLNext community (open source continuation) |
| Parent | Borland Software Corporation |
| Website | sourceforge |
The Object Windows Library (OWL) is a C++-based object-oriented application framework created by Borland Software Corporation to facilitate the development of desktop applications for Windows and selected OS/2 platforms.
Launched in 1991, OWL served as Borland's premier C++ framework until it was phased out in 1997, replaced by the Visual Component Library (VCL). OWL directly competed with Microsoft's Microsoft Foundation Class Library (MFC). The open-source initiative OWLNext continues to sustain OWL, ensuring its functionality with contemporary Windows operating systems and modern C++ compilers.
History
During the early 1990s, Borland was a dominant force in the C++ market. The release of Borland C++ 3.0 in 1991 included OWL 1.0, leveraging the industry's transition from C to C++ influenced by Windows and the rise of object-oriented programming. OWL rapidly became favored for developing Windows applications.
In 1992, Microsoft introduced MFC as part of Microsoft C++ 7.0, positioning it as OWL’s primary rival. OWL 1.0 employed Dynamic Dispatch Virtual Tables (DDVT), a proprietary extension to C++ that efficiently linked Windows messages to event handlers, whereas MFC avoided such language extensions.
Borland C++ 4.0, released in 1993, came with OWL 2.0 which replaced DDVT with response tables, a macro-based mechanism compatible with standard C++, resembling MFC’s approach. A conversion utility named OWLCVT helped developers migrate from OWL 1.0.
In April 1993, Borland collaborated with Novell to adapt OWL for Novell's cross-platform AppWare Foundation, targeting Macintosh, Windows, and Unix clients. However, following Novell CEO Raymond Noorda’s departure in 1994, AppWare development was discontinued, ending OWL support on that platform. In 1995, Software UNO provided a commercial port of OWL 2.0 (WM_MOTIF) for various UNIX systems including AIX, Solaris, and Linux.
Ahead of the Windows 95 release in 1995, Borland issued Borland C++ 4.5 featuring OWL 2.5 and pledged free updates to address compatibility concerns. Despite this effort, Microsoft Visual Studio had already overtaken Borland in market share by then, marking the beginning of OWL’s decline relative to MFC.
Borland C++ 5 arrived in 1996 accompanied by OWL 5, a significant redesign of the framework. This edition received only minor revisions and represented Borland’s final official OWL version.
In 1997, with the introduction of C++Builder, Borland discontinued Borland C++ and ended active development on OWL; the library was thereafter included solely as a supplementary CD with C++Builder.
By late 1999, Borland ceased all sales of Borland C++ and its associated OWL framework.
OWLNext
Following Borland’s withdrawal from OWL development, stewardship passed to a user community led by Yura Bidus. This effort evolved into the OWLNext open-source project hosted on SourceForge. OWLNext updates the library to maintain compatibility with current Windows editions and supports modern C++ compilers from Microsoft and Embarcadero Technologies.
Shipped releases
| Product version | OWL version |
|---|---|
| Borland C/C++ 3.0 | OWL 1.0 |
| Borland C/C++ 2.0 for OS/2 | OWL 2.0 |
| Borland C++ 4.0x | OWL 2.0 |
| Borland C++ 4.5x | OWL 2.5 |
| Borland C++ 5.0x | OWL 5.0 |
| Borland C++Builder 4.0 | OWL 5.0 |
| Borland C++Builder 5.0 | OWL 5.0 |
| CodeGear C++Builder 2007 | OWLNext 6.20 |
| Embarcadero C++Builder XE | OWLNext 6.30 |
| Embarcadero C++Builder XE2 | OWLNext 6.32 |
Subsequent versions of OWLNext have been distributed via SourceForge.
Additional resources
- Advanced OWL 5.0: Essential Tools for OWL Developers – Ted Neward, Manning, 1998.
- Borland C++ 4.x: Tips, Tricks, and Pitfalls – Clayton Walnum, 1994.
- Object-Oriented Programming with Borland C++ 4.5 – Ted Faison, 1995.
- Borland C++ 5.0 Programming Starter Kit Deluxe – Pearson Software, 2002.
- Borland C++ Object-Oriented Programming Examples – Ted Faison.
- Core OWL 5.0: In-Depth OWL Architecture – Ted Neward, 1998.
- Exploring the Object Windows Library – Ted Faison.
- Mastering Borland C++ 4.5 – Tom Swan, 1995.
- Programming with Object Windows 2.0 – Victor E. Broquard, 1993.
- Developing for OWL on Windows 95 – Victor E. Broquard, 1997.
- Teach Yourself OWL Programming in 21 Days – Ian Spencer, 1995.
- Windows Graphics Programming Using Borland C++ – Loren Heiny, 1994.