Arnold Trembley's Home Page


These pages were last updated Tuesday, September 27th, 2016.

Recently I have been working with GnuCOBOL (formerly OpenCOBOL), which looks like the free COBOL compiler for Windows that I have wanted for years. There will be a link for OpenCOBOL 1.1 (06FEB2009) below.

Some time ago I built the newer GnuCOBOL 1.1 compiler (20JAN2014) from source code available from the GnuCOBOL/OpenCOBOL project on The compiler has been tested with the GnuCOBOL version of the NIST (National Institute of Standards and Technology) COBOL85 test suite and passes 9,011 out of 9,129 test cases. Please see the link below for a Windows installer for GnuCOBOL 1.1.

There are also two versions of GnuCOBOL 2.0 with MinGW Release Candidate 1 (14AUG2016). One is built with Berkeley Database and the other is built with VBISAM2. Both versions have been updated with Gnu licensing information and additional documentation, and they may downloaded below.

There's a free Interactive Development Environment (IDE) for OpenCOBOL/GNUCOBOL written in Python, for Linux, Windows, and Mac OSX. The Windows installer includes GnuCOBOL 1.1 in addition to the IDE. This is probably the easiest way to get an easy-to-use COBOL compiler for Windows. You can also install GnuCOBOL 2.0 in another folder, and change the settings in "OpenCOBOLIDE" to use GnuCOBOL 2.0 instead of GnuCOBOL 1.1.

For anyone who might be interested, I have a version of the Unix CAL.EXE calendar utility, reimplemented in PowerBasic as PBCAL.EXE for 32-bit Windows XP or 64-bit Windows 7.
PBCAL.ZIP for Windows XP and Windows 7

As of Sun-21-Feb-2010, I have moved my pages to, since my previous provider no longer supports free personal web pages. I can also be found on LinkedIn and Facebook.

In 2007 I finally replaced Netscape with Mozilla Firefox and Thunderbird as my default browser and mail/news reader. And I've been trying to play the guitar again, but it is difficult to find enough time to practice. A good friend gave me a Fender Squire Stratocaster as an incentive. Recently, I've been having some fun playing Ukulele.

Occasionally I receive emails from programmers in India with COBOL questions, which is very gratifying to me. I hope the comments I provide to other working programmers are helpful.

For original work, I recommend my page on "COBOL Runtime Efficiency", which includes links to some additional performance anecdotes (including Leif Svalgaard's excellent article on Sorting Algorithms). The Programming Resources page has been updated to include links to GnuCOBOL/OpenCOBOL. There is also a sample COBOL program for converting IBM OS/VS COBOL source code to IBM VS/COBOL II source code.

You can read about distributed denial of service attacks at the Gibson Research Corporation website. I recommend this site to anyone with concerns about Internet privacy and security.

Please feel free to contact me at the following address: