# 14-online-cics — CICS Online Simulation

## 电信业务场景

在线客户照会(CICS模拟)。通过CALL/LINKAGE机制模拟CICS在线交易，客户服务人员可通过屏幕查询客户基本信息。

## Purpose
Simulates CICS transaction processing patterns using CALL/LINKAGE instead of EXEC CICS.

## Architecture
- **main-14-online-cics.cbl** — CICS simulation program (receives COMMAREA via CALL USING)
- **test-cics-driver.cbl** — Test driver that builds COMMAREAs and invokes the program

## Test Coverage
1. **INQY (Inquiry)** — COMMAREA receive, MAP file read, result output
2. **UPDT (Update)** — Process update function
3. **DEL (Delete)** — Process delete function
4. **UNKNOWN function** — Error handling for unrecognized function codes

## Key Techniques
- LINKAGE SECTION with CALL USING parameter passing
- COMMAREA simulation via 01-level structure
- MAPSEND/MAPRECV simulation via file I/O
- EVALUATE for function dispatch
- GOBACK to return to caller