DataReel Open Source Readme File

Overview
Features
License
Supported Platforms
Supported Compilers
Package Map
Example Programs
Version 6.2
Version 6.1
Version 6.0
Code Review and Fixes
Linux Builds
Windows Builds
Setup For Windows 11 desktop or Windows Server 2022/2025 development system

Overview

What is DataReel?
Datareel is a comprehensive cross-platform C++ development kit used to build multi-threaded database and communication applications. C++ is a programming language that produces fast executing compiled programs and offers very powerful programming capabilities. Unlike interpreted languages such as JAVA and PERL the C++ language by itself does not contain built-in programming interfaces for database, communications, and multi-threaded programming. By using DataReel you can extend the power of the C++ programming language by using high-level programming interfaces for database, communications, and multi-threaded programming.

The DataReel development package was produced by independent work and contract work released to the public through non-exclusive license agreements. The initial work began independently in 1997 and was augmented from 1999 to 2004 by code produced under contract to support various applications. Several developers throughout the World have made contributions to enhance the DataReel code and promote its stability. In 2005 the DataReel code library underwent intense analysis to produce a bulletproof code base suitable for use in complex commercial applications.

Why Use DataReel?
DataReel simplifies complex time consuming database, socket, and multi-threaded programming tasks by providing JAVA like programming interfaces for database, communications, and multi-threaded programming. Using DataReel you can harness the full power of the C++ programming language and build stable end-user applications, embedded systems, and reusable libraries for multiple operating systems.

DataReel is flexible. Using DataReel gives your developers the flexibility to develop core application components independently of complex user interfaces. DataReel is portable. DataReel not only offers portability but also interoperability between multiple platforms. DataReel is modular. DataReel is a modular approach to network and database programming making code adaptation and cross-platform testing easy.

Who Can Use DataReel?
The DataReel toolkit is available to commercial, individual, and academic developers. The DataReel code base is distributed to the public in an open source format. This keeps the code stable through the continued support of worldwide developers who submit code enhancements and report potential problems. The open source format is also intended to promote the C++ programming language as the language of choice for any programming task.

Who Can Contribute?
The DataReel project accepts bug fixes, enhancements, and additions from all developers. Source code releases are on the DataReel downloads page, and contributions are sent through the contact page.

Features

License

The DataReel open source library is copyrighted by DataReel Software Development, Copyright © 2001-2026, all rights reserved. DataReel open source is available to non-profit, commercial, individual, and academic developers. The open-source archive is distributed under the GNU Lesser General Public License (LGPL) with provisions for use in commercial and non-commercial applications under the terms of the LGPL.

Under the terms of the LGPL you can use the open source code in commercial applications as a static or dynamically linked library. This allows commercial developers to compile the library and link to it without making any changes to the DataReel source code.

GNU Lesser General Public License
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3.0 of the License, or (at your option) any later version.

This library 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. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, a copy is available on the gnu.org Website:

https://www.gnu.org/licenses/lgpl.html

Supported Platforms

The current Datareel release was developed and tested on Red Hat Enterprise Linux 10 (the default build platform), RHEL 9 and RHEL 8, Windows 11, and Windows Server 2022 and 2025. RHEL 6 and 7, and Windows releases older than Windows 11 and Windows Server 2022, are no longer supported.

On Linux the library uses the OpenSSL that comes with the operating system. On Windows use only an OpenSSL 3.5.x LTS release (see README_windows_openssl.txt). The Windows build is 64-bit by default, 32-bit builds are kept for legacy code only.

The datareel library can be compiled on any Linux variant with the GNU compiler.

The datareel library can be compiled for Windows using Microsoft's Visual Studio.

Legacy platforms in the code base include HPUX and Solaris but make files for legacy platforms are no longer distributed.

Datareel has been compiled for use in 16-bit, 32-bit, and 64-bit applications. The code base still supports 32-bit applications but current development is mainly for use in 64-bit applications.

Supported Compilers

For UNIX the current Datareel release supports GNU and Intel compiler builds. The code base has been used in super computer applications compiled with Cray C++ compilers.

For Windows the current Datareel release supports Microsoft Visual Studio 2022 or 2026.

Previous releases supported cross platform Windows builds using MSVC, Visual C++, BCC, and DJGPP.

Package Map

DataReel Directory Structure 

• bin - Directory used to intall executables
• docs - Directory for all DataReel documentation sets
• env - Makefile includes used to build libraries example programs
• examples_general - General support example programs
• examples_database - Database example programs
• examples_threads - Thread example programs
• examples_socket - Socket example programs
• include - DataReel include files
• lib - Empty directory used to install library files
• src - DataReel source code files
• utils - DataReel utility programs

Example Programs

The Datareel distribution contains several example programs. The examples are fully functional programs used to test and demonstrate each component of the library individually. The example programs are located within subdirectories of the "examples_general", "examples_database", "examples_threads", and "examples_socket" directories.

This HTML documentation set include many more example programs that can by used as templates to build applications. 

Version 6.2

DataReel 6.2, 10/25/2026, stops gxBtree walks and InfoHog data file scans from looping forever on damaged or crafted files, adds gxDatabase::SetWriteHook(), fixes the wxWidgets 3 headers, adds the __wxWIN3__ macro and adds a CMake build. The shared library is built as libdatareel.so.6.2. gxDatabase has two new members, so recompile and relink. See the DataReel 6.2 Release Notes. Every change in the source is marked with a "10/25/2026" comment.

Version 6.1

DataReel 6.1, 10/25/2026, is a security fix release. gxBtree and InfoHog now check the lengths and counts they read from database and index files, so a damaged or crafted file is rejected instead of overflowing memory. The shared library is built as libdatareel.so.6.1. There are no interface changes from 6.0; recompile and relink. Supported platforms are now RHEL 10, 9 and 8, Windows 11, and Windows Server 2022 and 2025. See the DataReel 6.1 Release Notes. Every change in the source is marked with a "10/25/2026" comment.

Version 6.0

DataReel 6.0, 10/24/2026, is the first major release in many years. Version 6.0 fixes every item that the 10/14/2026 code review left as is: linked list array cleanup, gxConfig::Add(), stopping threads when a thread pool is cleared, database cache Bind() and ReleaseSegments(), RDBMS duplicate key lookups and BLOB fields in all-field keys, mixed text in the XML parser, the RSS <cloud> element, the glibc robust mutex problem, and all -Wall -Wextra compiler warnings.

The shared library is built as libdatareel.so.6.0. Programs must be recompiled, and some interfaces changed. See the DataReel 6.0 Release Notes. Every change in the source is marked with a "10/24/2026" comment.

Code Review and Fixes

On 10/14/2026 the DataReel code in this repository was reviewed and fixed by Claude Code, Anthropic's AI coding assistant (https://claude.ai/code). The review covered compiler warnings, AddressSanitizer and UndefinedBehaviorSanitizer runs of the example programs, and valgrind checks. Fixes include:

• Mismatched new[]/delete calls in UString, strutil, gxDatabase, MemoryBuffer and other classes
• Undefined behavior in the gxINT16/32/64 byte packing, UString Find/IFind, and gxConfig::ChangeConfigLine()
• Bounds checks in POD, gxRDBMS and gxsXML, and leaked buffers in gxSocket
• Replaced the deprecated readdir_r() and _np robust mutex calls
• SSL updates for OpenSSL 3: a 2048-bit (RFC 7919 ffdhe2048) default DH group, OpenSSL 3 DH parameter and RSA key interfaces, error checking and cleanup on every path, and new ssl_server example keys, certificate and DH parameters
• New gxSSL class documentation
• New documentation pages for gxListB, the thread pool and thread helpers, the XML parser, the RSS feed writer, the RDBMS layer, the B-tree and database caches, the debug manager, ix_debug and the example programs, and a modern style for all documentation pages
• Fixes for bugs found while writing the new pages: the RDBMS layer, thread helpers and thread pool, XML parser and RSS writer, B-tree and database caches, debug manager, B-tree Find() and gxDatabase

These fixes are included in DataReel 6.0 and later.

See Code Review and Fixes for the full list of fixes, SSL updates and behavior changes. Every change in the source is marked with a "10/14/2026" comment.

Linux Builds

Example install and build:

> mkdir -pv ~/git
> cd ~/git
> wget https://datareel.com/downloads/datareel/datareel-<version>.tar.gz
> tar xzf datareel-<version>.tar.gz
> mv datareel-<version> datareel
> cd datareel
> cd env

In the env directory edit the linux.env file if you need to make any adjustments or modifications to the build 

> source gnu_env.sh
> cd ../build
> make 
> make install
> make clean

SSL is built into the libdatareel library with OpenSSL by default. The OpenSSL development files must be installed (libssl-dev on Debian and Ubuntu, openssl-devel on RHEL and Fedora). Linux builds always use the operating system's OpenSSL; do not build against a private OpenSSL copy on Linux or mix it with the system version. On a system without OpenSSL build with:

> make USE_OPEN_SSL=NO
> make USE_OPEN_SSL=NO install
> make USE_OPEN_SSL=NO clean

To build example programs:

> cd ~/git/datareel/examples_database
> ls -l 
> cd simple
> make

To build utility programs

> cd ~/git/datareel/utils
> ls
> cd hexdump
> make 

Windows Builds

In the example build below we will assume you are working with a copy of the datareel library unpacked to the "%USERPROFILE%\datareel" location.

In this document we will assume you have installed Visual Studio 2026 and will be working on the command line.

To setup a command line build open a Run dialog and enter cmd to open a command prompt.

To setup the VS 2026 environment the msvc.bat file is provided in the env directory. The default build is 64-bit x64. For 32-bit x86 builds of legacy code use env\msvc32_vs2026.bat instead of env\msvc.bat.

SSL is built into the gxcode library. By default the gxSSL class uses the native Windows Schannel (SSPI) TLS API, so OpenSSL is not needed. OpenSSL is still available as an option for existing code, see below. When you build with OpenSSL on Windows, use only an OpenSSL 3.5.x LTS (long term support) release, 64-bit by default and 32-bit for legacy builds. See README_windows_openssl.txt.

To build the datareel static library:

> cd %USERPROFILE%\datareel
> env\msvc.bat
> cd winslib
> nmake -f msvc.mak

The utility programs and examples programs will link to the static library. Programs link to secur32.lib, crypt32.lib, and ncrypt.lib for SSL, which are part of the Windows SDK.

To build the example programs:

> cd %USERPROFILE%\datareel\examples_general
> cd string_class
> nmake -f msvc.mak

> cd %USERPROFILE%\datareel\examples_socket
> cd https_client
> nmake -f msvc.mak

To build the datareel library as a DLL:

> cd %USERPROFILE%\datareel
> env\msvc.bat
> cd dll
> nmake -f msvc.mak

To build the datareel static library with OpenSSL instead of Schannel:

> cd %USERPROFILE%\datareel
> env\msvc.bat
> cd winslib
> notepad openssl.env

In the openssl.env file set the path to your OpenSSL 3.5.x LTS installation directory (3plibs\openssl64 by default, or 3plibs\openssl32 for a legacy 32-bit build).

> nmake -f msvc_ssl.mak

Programs that link to the OpenSSL build of the library must also be built with USESSL=1. Set the path to your OpenSSL 3.5.x LTS install in the following ENV file:

> cd %USERPROFILE%\datareel\env
> notepad openssl_windows.env

Then build your program or an example program with USESSL=1:

> cd %USERPROFILE%\datareel\examples_socket
> cd https_client
> nmake -f msvc.mak USESSL=1

Before running the example program in you user environment add the OpenSSL 3.5.x bin dir to your PATH:

> set PATH=%PATH%;e:\3plibs\openssl64\bin

To build the datareel library as a DLL with OpenSSL:

> cd %USERPROFILE%\datareel
> env\msvc.bat
> cd dll
> notepad openssl.env

In the openssl.env file set the path to your OpenSSL 3.5.x LTS installation directory (3plibs\openssl64 by default, or 3plibs\openssl32 for a legacy 32-bit build).

> nmake -f msvc_ssl.mak

See README_windows_openssl.txt for building OpenSSL 3.5.x LTS on Windows.

DataReel Copyright © 2001-2026 DataReel Software Development