Rexx

Rexx (restructured extended executor) is a high-level programming language made by Mike Cowlishaw at IBM. It is both private and open source, and there are many versions for different kinds of computers. People use Rexx to write small programs called scripts, make shortcuts called macros, and build bigger applications.

Rexx works well in many different places. It is the main scripting language in operating systems like OS/2, MVS, VM, and AmigaOS. It is also used to create macros in programs such as SPF/PC, KEDIT, THE, and ZOC. With the right tools, Rexx can also work with Windows programs.

A Rexx script is connected to a Rexx interpreter when it runs. On large IBM mainframe computers, these scripts are sometimes called EXEC files. On OS/2, Rexx scripts use the ".cmd" ending, like other scripts. On Linux, Rexx scripts usually start with a special line called a shebang. Each program that can use Rexx macros has its own rules for naming those macros.

Name

The language was first called REX, short for Reformed Executor. Later, an extra "X" was added to prevent confusion with other products. The name was always written in uppercase letters. Mike Cowlishaw's books about the language used the all-caps name, REXX. In 1984, the system product used a new name that matched the abbreviation, REstructured eXtended eXecutor.

History

pre–1990

Mike Cowlishaw created Rexx in his free time between March 1979 and mid-1982. He wanted to make a simpler language to replace EXEC and EXEC 2. Rexx was first shown publicly in 1981 at a conference in Houston, Texas, and became an IBM product in 1982.

Over the years, IBM included Rexx in many of its operating systems like VM/CMS, MVS TSO/E, IBM OS/400, and others. Rexx was also made available for many other systems, including Novell NetWare, Windows, Java, and Linux.

Since 1990

In 1990, the first independent Rexx meeting was organized, leading to the creation of the Rexx Language Association. Meetings have been held every year since then.

In 1992, two popular open-source versions of Rexx were created for Unix and Windows. More versions of Rexx have been developed for many different systems over the years. In 1996, a standard for Rexx was published by the American National Standards Institute.

In 2004, IBM announced plans to release their Object REXX under an open license. In 2005, the first public version of Open Object Rexx was released, allowing Rexx to be used for programming Windows and applications. In 2019, a meeting celebrated the 40th anniversary of Rexx in England, where it was first created.

Toolkits

Rexx has many useful tools. RexxUtil helps with files, folders, and system tasks. Rexx/Tk is a graphics toolkit that works like Tcl/Tk. RexxEd is an integrated development environment for Windows. Other tools include RxSock for network communication, and a Rexx interpreter that works on the Windows command line and in DOS.