Operational Control Language (OCL) is the control language of the IBM System/34 and System/36 minicomputer family. Other control languages include CL (System/38 and AS/400), JCL (System/370), and REXX (AS/400). The facility of DOS to use batch files is also control language.
On the IBM S/34 and S/36, OCL statements are used to directly load user or system programs into memory, assign system resources to them, and transfer system control to them in a process called execution. The fact that a program is on a computer's disk drive does not in itself cause the computer to begin working on the program.
OCL statements can be entered from the keyboard, but are generally stored in a S/34-S/36 procedure member. A procedure member is a freely editable member within a library, not dissimilar from a source member. On the S/34-S/36, procedures are not compiled.
OCL statements begin with two slashes and a space. Here's an example of a short procedure stored on a System/36 as PROC1:
In this short procedure, a number of OCL statements and procedure control expressions (PCE) are used. Comments are represented by an asterisk in column 1, or can be placed after the end of a statement.