64-bit Native COBOL Programming

Restriction: The following information applies to native COBOL only.

For information about .NET COBOL applications running on a 64-bit platform, see 64-Bit Applications in the .NET Environment.

As 64-bit architecture is becoming increasingly prevalent, the consideration of moving towards producing 64-bit applications is also increasing. Many of the major operating system vendors now default to 64-bit support, and whilst still supporting the running of 32-bit applications, have signalled intent to stop supporting the building of 32-bit applications on future platforms.

Visual COBOL makes it easy for you to take advantage of the benefits that 64-bit programming offers. The IDE and command line tools both enable you to compile your source code to target both a 64-bit and a 32-bit run-time environment, and Enterprise Server provides both a 32-bit and 64-bit execution environment.

Existing 32-bit applications (applications compiled with the 32-bit Compiler) can still run in a 64-bit run-time environment, but they will not be taking advantage of the benefits of 64-bit programming. When you compile a native COBOL program with the 64-bit Compiler, its elements are addressed using 64-bit pointers, which enables you to point to virtual address ranges in memory that are greater than 4GB in size (a limit of 32-bit pointers). The increased range can result in significantly improved processing times for certain types of programs (for example, computational programs). 64-bit programs are only designed to run in 64-bit run-time environments.

If you intend to transition your existing code to a 64-bit environment, Visual COBOL contains a number of features that help make it easier, such as prototyping of library routines. It also provides analysis tooling for Windows environments that helps identify potential issues with your code, before you deploy.

There are other considerations when preparing to move your applications to a 64-bit environment, such as the compatibility of third-party applications, plugins, hardware, etc.... You will almost certainly need to ensure that a 64-bit driver is used to interact with that software or hardware; for example, if connecting to a database or printer, you will now need a 64-bit driver in order to interact. This consideration is not just limited to Visual COBOL, but when moving to a 64-bit environment as a whole.