What does CL Control Language Look Like?
Quite simply CL is a very structured, very readable scripting language that is easy to write and east to understand.
From simple CL like this:
To more complex CL like this:
Control Language (CL) has a clean, command‑driven structure that’s easy to read once you get used to its style. A CL program is made up of simple, English‑like commands each one performing a specific task on the IBM i system. Most commands follow a verb–noun pattern, such as SNDMSG (Send Message), CPYF (Copy File), or DLTF (Delete File). Parameters are written in a keyword format, making the intent of each line very clear.
A typical CL program begins with a program declaration, followed by a sequence of operational commands. It often includes conditional logic, loops, and calls to RPG or other programs. Here’s a small example to illustrate the look and feel:
DCL VAR(&COUNT) TYPE(*DEC) LEN(3 0)
CHGVAR VAR(&COUNT) VALUE(0)
LOOP:
CHGVAR VAR(&COUNT) VALUE(&COUNT + 1)
SNDPGMMSG MSG('Loop iteration:' *BCAT &COUNT)
IF COND(&COUNT < 5) THEN(GOTO LOOP)
ENDPGM
This snippet shows the core characteristics of CL:
- Uppercase commands that describe exactly what they do
- Keyword‑driven parameters for clarity
- Structured flow using labels, loops, and conditions
- A procedural, step‑by‑step feel that mirrors how the IBM i operates
CL is intentionally straight-forward. It's designed to automate tasks, control jobs, manage files, and orchestrate system operations. Once you see a few examples, its style becomes instantly recognizable.