# Generated-source output (llmcpp)

**Generated-source output** writes ordinary C++ after llmcpp has replaced annotated requests with accepted implementations. It allows review without immediately building the final executable.

```bash
$ llmc++     --llm     -fllm-offline     main.cpp
```

This writes `main.llm.cpp`, using cached bodies and stopping before native compilation. An output filename ending in `.cpp`, `.cc`, or `.cxx` also selects generated-source mode, allowing an explicit destination with `-o`.

The rewritten file contains the implementation that conventional compilation will consume. Read it for edge cases, error handling, mutation, and dependency assumptions. It can also be compiled with an ordinary C++ compiler configured for the source's requirements.

Offline mode is useful during review because it requires the existing cached implementation rather than generating a replacement on a miss. Omit that setting only when fresh generation is intended.

Keeping the rewritten source produces an artifact independent of later generation exchanges. It does not establish [[llmcpp-behavioral-correctness|behavioral correctness]]: the implementation still needs tests against the intended contract, just like manually written C++.