What is OpenCOBOL?

[Anuj Dhawan]

OpenCOBOL

OpenCOBOL: An OverviewIntroduction to OpenCOBOLOpenCOBOL is a robust and widely used open-source COBOL compiler that provides a modern implementation of the COBOL programming language. It is an important tool for software developers and enterprises that continue to rely on COBOL-based applications, ensuring compatibility with legacy systems while leveraging contemporary computing platforms.COBOL (Common Business-Oriented Language) has been a staple in enterprise computing since its inception in the late 1950s. It has powered mission-critical applications in industries such as banking, insurance, government, and retail. Despite the rise of newer programming languages, COBOL remains highly relevant due to the vast volume of existing COBOL code that continues to run crucial business operations worldwide.OpenCOBOL serves as a bridge between traditional COBOL applications and modern computing environments. By offering an open-source alternative to proprietary COBOL compilers, OpenCOBOL provides developers with a cost-effective, flexible, and community-supported option for maintaining and evolving COBOL applications.

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Standards and CompatibilityOpenCOBOL implements a substantial part of the COBOL 85 and COBOL 2002 standards, making it a highly compatible solution for legacy COBOL codebases. It also incorporates numerous extensions from existing COBOL compilers, such as those developed by IBM, Micro Focus, and Fujitsu. These extensions help ensure that programs written in proprietary COBOL dialects can be compiled and executed with minimal modifications.The COBOL 85 standard introduced structured programming constructs, which improved code readability and maintainability. COBOL 2002 brought further enhancements, such as support for object-oriented programming (OOP) and user-defined functions. OpenCOBOL’s implementation of these standards allows it to support both traditional procedural COBOL programs and more modern, object-oriented COBOL applications.By maintaining compatibility with a broad spectrum of COBOL features, OpenCOBOL enables developers to modernize and transition legacy applications without significant code rewrites. This capability is particularly valuable for enterprises that depend on COBOL for critical business functions but seek to modernize their IT infrastructure.

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Compilation Process: COBOL to C to Machine CodeOne of the defining characteristics of OpenCOBOL is its compilation process. Instead of compiling COBOL code directly into machine code, OpenCOBOL translates COBOL programs into C. The resulting C code is then compiled using the native C compiler of the host system.This two-step compilation process offers several advantages:

1. Portability: By leveraging a C compiler, OpenCOBOL can generate executable code for a wide range of platforms, including Unix/Linux, macOS, and Microsoft Windows.
2. Optimization: Modern C compilers, such as GCC and Clang, are highly optimized and produce efficient machine code. OpenCOBOL benefits from the ongoing advancements in C compiler technology.
3. Interoperability: The translation to C enables better integration with other C and C++ applications, allowing COBOL programs to call C functions and vice versa. This interoperability is particularly useful for extending COBOL applications with modern programming features.

The OpenCOBOL compiler is designed to work seamlessly with standard C development tools, making it a versatile solution for developers working in mixed-language environments.

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​​​​​​​Platform SupportOne of the key strengths of OpenCOBOL is its ability to run on multiple platforms. It supports:

• Unix/Linux: OpenCOBOL is widely used in Unix and Linux environments, making it a preferred choice for businesses that rely on COBOL applications running on mainframes or Unix-based servers.
• Mac OS X: OpenCOBOL can be installed and used on macOS, providing a development environment for COBOL programmers who prefer Apple’s ecosystem.
• Microsoft Windows: OpenCOBOL is also compatible with Windows, allowing developers to compile and run COBOL applications on Windows-based systems. This is particularly useful for organizations that maintain COBOL applications in mixed operating system environments.

The ability to deploy COBOL applications across multiple operating systems makes OpenCOBOL an attractive choice for organizations looking to maintain platform independence while ensuring business continuity.

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​​​​​​​Licensing and Open-Source NatureOpenCOBOL is licensed under the GNU General Public License (GPL), which means that the compiler itself is freely available for use, modification, and distribution. The runtime library, which is required to execute compiled COBOL programs, is licensed under the GNU Lesser General Public License (LGPL). This distinction allows developers to use OpenCOBOL in both open-source and proprietary software projects while maintaining compliance with licensing terms.By being open-source, OpenCOBOL benefits from community contributions, ensuring continuous improvements, bug fixes, and feature enhancements. Developers and organizations can actively participate in its development, making OpenCOBOL a dynamic and evolving solution for COBOL programming.

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​​​​​​​Key Features of OpenCOBOL

1. Supports COBOL 85 and COBOL 2002 Standards: Ensures compatibility with most existing COBOL programs and allows modern COBOL development.
2. COBOL to C Translation: Enhances portability, optimization, and integration with C-based applications.
3. Multi-Platform Support: Runs on Unix/Linux, macOS, and Windows, offering flexibility for diverse IT environments.
4. Extensive Compiler Extensions: Implements features from other COBOL compilers, reducing migration challenges for legacy applications.
5. Interoperability with C: Facilitates the use of C functions within COBOL programs and vice versa.
6. Active Open-Source Community: Benefits from continuous improvements and contributions from developers worldwide.
7. Flexible Licensing: Available under GPL for the compiler and LGPL for the runtime library, ensuring accessibility for both open-source and proprietary use cases.

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​​​​​​​Use Cases and ApplicationsOpenCOBOL is widely used in various industries and application domains, including:

• Enterprise Legacy System Maintenance: Many large organizations still rely on COBOL for critical business applications. OpenCOBOL allows them to maintain and enhance these systems cost-effectively.
• COBOL Modernization: OpenCOBOL facilitates the transition of COBOL applications to modern computing environments while retaining legacy code.
• COBOL Learning and Education: As an open-source COBOL compiler, OpenCOBOL provides an accessible learning platform for students and new developers interested in COBOL.
• Integration with Modern Technologies: OpenCOBOL’s ability to work with C enables businesses to extend COBOL applications with modern functionalities and integrate with newer systems.

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​​​​​​​Conclusion
​​​​​​​OpenCOBOL is a powerful, flexible, and open-source COBOL compiler that ensures the longevity and adaptability of COBOL applications. By implementing key COBOL standards, supporting multiple platforms, and providing interoperability with C, OpenCOBOL empowers businesses to maintain and modernize their COBOL-based systems efficiently.Its open-source nature and active community support make it an excellent choice for organizations and developers looking to leverage COBOL while embracing modern software development practices. Whether for legacy system maintenance, modernization, or educational purposes, OpenCOBOL remains a crucial tool in the world of COBOL programming.

[Anuj Dhawan]

As I said earlier the compiler for OpenCOBOL is licensed under GNU General Public License. And the run-time library is licensed under GNU Lesser General Public License. Well having said all that -- What that means, anyways!? This is directly from the horse's mouth:

One is allowed to write OpenCOBOL programs that use the libcob run time library the way you like. The closed, proprietary, commercial use of it is allowed and encouraged. You can ship programs in binary form as you wish. Modifications to the compiler itself, MUST provide access to source code and be licensed under the GNU GPL. This ensures that no one is allowed to call modified sources their own, nor deny anyone else the chance to copy and re-distribute the compiler source code, including your local changes.

Please note: any version of the compiler that is configured to use Berkeley DB beyond version 1.85 must abide by the Oracle license and sources of the COBOL programs that use libdb must be shipped with any binaries. OpenCOBOL is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.