example/client-c-example/README.md

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# How to get a complete C client demo project (SessionC)

Pure **C** examples for the IoTDB Session **C API** (`SessionC.h`): **tree model** (`tree_example`) and **table model** (`table_example`). Default connection: `127.0.0.1:6667`, user `root` / password `root` (edit the macros at the top of each `.c` file).

## Get a project

Using Maven to build this example project (requires **Boost**, same as the C++ client; on Windows see [`iotdb-client/client-cpp/README.md`](../../iotdb-client/client-cpp/README.md)):

* `cd` the root path of the whole project
* run  
  `mvn package -DskipTests -P with-cpp -pl example/client-c-example -am`  
  (use `mvn clean package ...` when no other process holds files under `iotdb-client/client-cpp/target`; on Windows add Boost paths, e.g.  
  `-D"boost.include.dir=C:\local\boost_1_87_0" -D"boost.library.dir=C:\local\boost_1_87_0\lib64-msvc-14.2"`)
* `cd example/client-c-example/target`

After a successful build you should have:

* Unpacked C++ client headers and libraries under `client/` and Thrift under `thrift/` (same layout as [client-cpp-example](../client-cpp-example/README.md))
* CMake-generated binaries, for example on Windows MSVC:  
  `Release/tree_example.exe`, `Release/table_example.exe`  
  (exact path depends on the CMake generator)

## Run

Start IoTDB first, then:

```text
# Windows (example)
Release\tree_example.exe
Release\table_example.exe
```

On failure, the programs print to `stderr` and you can inspect `ts_get_last_error()`.

## Source layout

```
example/client-c-example/
+-- README.md
+-- pom.xml
+-- src/
|   +-- CMakeLists.txt
|   +-- tree_example.c
|   +-- table_example.c
```

The Maven build copies `src/*.c` and `src/CMakeLists.txt` into `target/` next to the unpacked `client/` and `thrift/` trees, then runs CMake to compile the two executables.