OS 2200
OS 2200 is the operating system for the Unisys ClearPath Dorado family of mainframe systems. The operating system kernel of OS 2200 is a lineal descendant of Exec 8 for the UNIVAC 1108.
Documentation and other information on current and past Un ...
has had several generations of compilers and linkers in its history supporting a wide variety of
programming language
A programming language is a system of notation for writing computer programs. Most programming languages are text-based formal languages, but they may also be graphical. They are a kind of computer language.
The description of a programming l ...
s. In the first releases, the
Exec II assembler (SLEUTH) and compilers were used. The assembler was quickly replaced with an updated version (ASM) designed specifically for the 1108 computer and
Exec 8 but the early compilers continued in use for quite some time.
Universal Compiling System
The modern compiling system for OS 2200 is known as UCS, Universal Compiling System. The UCS architecture uses a common syntax analyzer, separate semantic front ends for each language and a common back-end and optimizer. There is also a common language runtime environment. The UCS system was developed starting in 1969 and initially included
PL/I
PL/I (Programming Language One, pronounced and sometimes written PL/1) is a procedural, imperative computer programming language developed and published by IBM. It is designed for scientific, engineering, business and system programming. It ...
and
Pascal.
FORTRAN and
COBOL
COBOL (; an acronym for "common business-oriented language") is a compiled English-like computer programming language designed for business use. It is an imperative, procedural and, since 2002, object-oriented language. COBOL is primarily ...
were soon added.
Ada was added later. The currently supported languages include COBOL, FORTRAN,
C, and PLUS. PLUS, Programming Language for Unisys (originally UNIVAC) Systems, is a block structured language somewhat similar to Pascal which it predates.
Legacy compilers
Previous PLUS, COBOL and FORTRAN compilers are also still supported. An even earlier FORTRAN compiler (FORTRAN V), while no longer supported, is still in use for an application developed in the 1960s in that language.
Compilers previously existed for
ALGOL
ALGOL (; short for "Algorithmic Language") is a family of imperative computer programming languages originally developed in 1958. ALGOL heavily influenced many other languages and was the standard method for algorithm description used by th ...
,
Simula
Simula is the name of two simulation programming languages, Simula I and Simula 67, developed in the 1960s at the Norwegian Computing Center in Oslo, by Ole-Johan Dahl and Kristen Nygaard. Syntactically, it is an approximate superset of AL ...
,
BASIC
BASIC (Beginners' All-purpose Symbolic Instruction Code) is a family of general-purpose, high-level programming languages designed for ease of use. The original version was created by John G. Kemeny and Thomas E. Kurtz at Dartmouth College ...
,
Lisp
A lisp is a speech impairment in which a person misarticulates sibilants (, , , , , , , ). These misarticulations often result in unclear speech.
Types
* A frontal lisp occurs when the tongue is placed anterior to the target. Interdental lispi ...
,
NELIAC,
JOVIAL, and other programming languages that are no longer in use on the ClearPath OS 2200 systems.
Assembler
The assembler, MASM, is heavily used both to obtain the ultimate in efficiency and to implement system calls that are not native to the programming language. Much of the MASM code in current use is a carryover from earlier days when compiler technology was not as advanced and when the machines were much slower and more constrained by memory size than today.
Linking
There are two linking systems used. The collector (@MAP) combines the output relocatable elements of the basic-mode compilers and assemblers into an absolute element which is directly executable. While this linker is intended primarily to support basic mode, the relocatable and absolute elements may contain extended-mode as well. This is often the case when an existing application is enhanced to use extended mode or call extended mode libraries but still contains some basic mode code. The Exec is an example of such a program.
The linker (@LINK) is the modern linking environment which combines object modules into a new object module. It provides both static and dynamic linking capabilities. The most common usage is to combine the object modules of a program statically but to allow dynamic linking to libraries.
Java
OS 2200 provides a complete
Java
Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mo ...
environment.

Java on OS 2200 has evolved from an interesting additional capability for small servlets and tools to a full environment capable of handling large applications. The Virtual Machine for the Java Platform on ClearPath OS 2200 JProcessor is a
Linux
Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which i ...
port of the
Oracle Corporation
Oracle Corporation is an American multinational computer technology corporation headquartered in Austin, Texas. In 2020, Oracle was the third-largest software company in the world by revenue and market capitalization. The company sells da ...
Java release. The environment includes a full
J2EE
Jakarta EE, formerly Java Platform, Enterprise Edition (Java EE) and Java 2 Platform, Enterprise Edition (J2EE), is a set of specifications, extending Java SE with specifications for enterprise features such as distributed computing and web ser ...
application server environment using the
Tomcat open source web server from the
Apache Software Foundation and the
JBoss application server.
All of this has been integrated with the OS 2200 security, databases, and recovery environment.
References
{{DEFAULTSORT:Unisys Os 2200 Programming Languages
Unisys software