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Wikipedia
Fox Pro was a text-based proce durally oriented programming language and database management system (DBMS), and it was also an object-oriented programming language, originally published by Fox Software and later by Microsoft, for MS-DOS, Windows, Macintosh, and UNIX. The final published release of Fox Pro was 2.6. Development continued under the Visual Fox Pro label, which in turn was discontinued in 2007.
Fox Pro was derived from Fox Base (Fox Software, Perrys burg, Ohio), which was in turn derived from dBase III (Ashton-Tate) and dBase II. dBase II was the first commercial version of a database program written by Wayne Ratliff, called Vulcan, running on CP/M, as does dBase II.
Fox Pro was both a DBMS and a relational database management system (RDBMS), since it extensively supported multiple relationships between multiple DBF files (tables). However, it lacked transactional processing.
Fox Pro was sold and supported by Microsoft after they acquired Fox Software in its entirety in 1992. At that time there was an active worldwide community of Fox Pro users and programmers. Fox Pro 2.6 for UNIX (FPU26) has even been successfully installed on Linux and FreeBSD using the Intel Binary Compatibility Standard (ibcs2) support library.
FoxPro 2 included the “Rushmore” optimizing engine, which used indices to accelerate data retrieval and updating. Rushmore technology examined every data-related statement and looked for filter expressions. If one was used, it looked for an index matching the same expression.
FoxPro 2 was originally built on Watcom C/C++, which used the DOS/4GW memory extender to access expanded and extended memory. It could also use almost all available RAM even if no HIMEM.SYS was loaded.
It was derived from Fox Pro (originally known as Fox BASE) which was developed by Fox Software beginning in 1984. Fox Technologies merged with Microsoft in 1992, after which the software acquired further features and the prefix “Visual”. FoxPro 2.6 worked on Mac OS, DOS, Windows, and Unix.
Visual Fox Pro 3.0, the first “Visual” version, reduced platform support to only Mac and Windows, and later versions 5, 6, 7, 8 and 9 were Windows-only. The current version of Visual FoxPro is COM-based and Microsoft has stated that they do not intend to create a Microsoft .NET version.
Version 9.0, released in December 2004 and updated in October 2007 with the SP2 patch, was the final version of the product.
Visual FoxPro originated as a member of the class of languages commonly referred to as “xBase” languages, which have syntax based on the dBase programming language. Other members of the xBase language family include Clipper and Recital (database).
Visual FoxPro, commonly abbreviated as VFP, is tightly integrated with its own relational database engine, which extends FoxPro’s xBase capabilities to support SQL query and data manipulation. Unlike most database management systems, Visual FoxPro is a full-featured, dynamic programming language that does not require the use of an additional general-purpose programming environment. It can be used to write not just traditional “fat client” applications, but also middleware and web applications.
In late 2002, it was demonstrated that Visual Fox Pro can run on Linux under the Wine Windows compatibility suite. In 2003, this led to complaints by Microsoft: it was claimed that the deployment of runtime Fox Pro code on non-Windows machines violates the End User License Agreement.
Visual FoxPro had a rapid rise and fall in popularity as measured by the TIOBE Programming Community Index. In December 2005, VFP broke into the top 20 for the first time. In June 2006 it peaked at position 12, making it (at the time) a “B” language. As of October 2019, Visual FoxPro holds position 51 on the TIOBE index.
In March 2007, Microsoft announced that there would be no VFP 10, thus making VFP9 (released to manufacturing on December 17, 2004) the last commercial VFP release from Microsoft. Service Pack 2 for Microsoft Visual FoxPro 9.0 was released on October 16, 2007. The support of Version 9 ended on January 13, 2015.
At the time of the end of life announcement, work on the next release codenamed Sedna (named after a recently discovered dwarf planet) which was built on top of the VFP 9 code base had already begun. “Sedna” is a set of add-ons to VFP 9.0 of x Base components to support a number of interoperability scenarios with various Microsoft technologies including SQL Server 2005, .NET Framework, Windows Vista, Office 2007, Windows Search and Team Foundation Server (TFS). Microsoft released Sedna under the Shared source license on the Code Plex site. Microsoft has clarified that the VFP core will still remain closed source. Sedna was released on January 25, 2008. As of March 2008, all x Base components of the VFP 9 SP2 (including Sedna) were available for community-development on Code Plex.
In late March 2007 a grassroots campaign was started by the Spanish-speaking Fox Pro community at Más Fox Pro (“More Fox Pro” in English) to sign a petition to Microsoft to continue updating Visual FoxPro or release it to the community as open-source. On April 3, 2007 the movement was noted by the technical press.
On April 3, 2007, Microsoft responded to the petition with this statement from Alan Griver:
“We’re very aware of the FoxPro community and that played a large part in what we announced on March 13th. It’s never an easy decision to announce that we’re not going to release another version of a product and it’s one that we consider very carefully.
“We’re not announcing the end of Fox Pro: Obviously, Fox Pro applications will continue to work. By some of our internal estimates, there are more applications running in Fox Pro 2.6 than there are in VFP and Fox Pro 2.6 hasn’t been supported in many years. Visual Fox Pro 9 will be supported by Microsoft through 2015.
“For Microsoft to continue to evolve the Fox Pro base, we would need to look at creating a 64-bit development environment and that would involve an almost complete rewrite of the core product. We’ve also invested in creating a scalable database with SQL Server, including the freely available SQL Server Express Edition. As far as forming a partnership with a third-party is concerned, we’ve heard from a number of large Fox Pro customers that this would make it impossible for them to continue to use Fox Pro since it would no longer be from an approved vendor. We felt that putting the environment into open source on Code Plex, which balances the needs of both the community and the large customers, was the best path forward.”
- VFP has an extensive library of predefined classes and visual objects which are accessed in the IDE by a Property Sheet (including Methods), so code such as the above defining classes and objects are only needed for special purposes and the framework of large systems.