Work Flow Language
Encyclopedia
Work Flow Language, or WFL ("wiffle") is the process control
language for the Burroughs large systems, including the Unisys
ClearPath/MCP series, and their operating system
Master Control Program. Developed soon after the B5000 in 1961, WFL is the ClearPath equivalent of the Job Control Language
(JCL) on IBM
mainframes and the shell script
s of Unix-like
operating systems. Unlike JCL, WFL is a high-level structured language complete with subroutine
s (procedures and functions) with arguments
and high-level program control flow
instructions. WFL programs are compiled
to binary executables like any other MCP subject.
WFL is used for high-level system operations, such as running tasks, moving and copying files, providing high-level recoverability. Thus it is not a general purpose language in that you would not use it to do general computations. You can open and close files to check their attributes for example; however, you cannot read or change their contents in WFL – that you do in a general purpose language, and invoke it as a task from WFL.
WFL has a high-level ALGOL
-like readable syntax. It has none of the low-level assembler-like commands of JCL like
WFL also has an instruction block command which is used to give operators instructions needed to run the current job. These instructions are displayed using the 'IB' operator command.
Process control
Process control is a statistics and engineering discipline that deals with architectures, mechanisms and algorithms for maintaining the output of a specific process within a desired range...
language for the Burroughs large systems, including the Unisys
Unisys
Unisys Corporation , headquartered in Blue Bell, Pennsylvania, United States, and incorporated in Delaware, is a long established business whose core products now involves computing and networking.-History:...
ClearPath/MCP series, and their operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
Master Control Program. Developed soon after the B5000 in 1961, WFL is the ClearPath equivalent of the Job Control Language
Job Control Language
Job Control Language is a scripting language used on IBM mainframe operating systems to instruct the system on how to run a batch job or start a subsystem....
(JCL) on IBM
IBM
International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...
mainframes and the shell script
Shell script
A shell script is a script written for the shell, or command line interpreter, of an operating system. It is often considered a simple domain-specific programming language...
s of Unix-like
Unix-like
A Unix-like operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification....
operating systems. Unlike JCL, WFL is a high-level structured language complete with subroutine
Subroutine
In computer science, a subroutine is a portion of code within a larger program that performs a specific task and is relatively independent of the remaining code....
s (procedures and functions) with arguments
Parameter (computer science)
In computer programming, a parameter is a special kind of variable, used in a subroutine to refer to one of the pieces of data provided as input to the subroutine. These pieces of data are called arguments...
and high-level program control flow
Control flow
In computer science, control flow refers to the order in which the individual statements, instructions, or function calls of an imperative or a declarative program are executed or evaluated....
instructions. WFL programs are compiled
Compiler
A compiler is a computer program that transforms source code written in a programming language into another computer language...
to binary executables like any other MCP subject.
WFL is used for high-level system operations, such as running tasks, moving and copying files, providing high-level recoverability. Thus it is not a general purpose language in that you would not use it to do general computations. You can open and close files to check their attributes for example; however, you cannot read or change their contents in WFL – that you do in a general purpose language, and invoke it as a task from WFL.
WFL has a high-level ALGOL
ALGOL
ALGOL is a family of imperative computer programming languages originally developed in the mid 1950s which greatly influenced many other languages and became the de facto way algorithms were described in textbooks and academic works for almost the next 30 years...
-like readable syntax. It has none of the low-level assembler-like commands of JCL like
//SYSIN DD, etc in order to connect hardware devices and open files for programs. All WFL constructs deal with the high-level abstractions of tasks and files. Parameters are also real HLL parameters, not the $1, $2... style position parameters of shell scripts.WFL also has an instruction block command which is used to give operators instructions needed to run the current job. These instructions are displayed using the 'IB' operator command.