# {py:mod}`ros_sugar.robot.shm`

```{py:module} ros_sugar.robot.shm
```

```{autodoc2-docstring} ros_sugar.robot.shm
:allowtitles:
```

## Module Contents

### Classes

````{list-table}
:class: autosummary longtable
:align: left

* - {py:obj}`ShmDescriptor <ros_sugar.robot.shm.ShmDescriptor>`
  - ```{autodoc2-docstring} ros_sugar.robot.shm.ShmDescriptor
    :summary:
    ```
* - {py:obj}`ShmRingWriter <ros_sugar.robot.shm.ShmRingWriter>`
  - ```{autodoc2-docstring} ros_sugar.robot.shm.ShmRingWriter
    :summary:
    ```
* - {py:obj}`ShmReaderCache <ros_sugar.robot.shm.ShmReaderCache>`
  - ```{autodoc2-docstring} ros_sugar.robot.shm.ShmReaderCache
    :summary:
    ```
* - {py:obj}`PluginShmManager <ros_sugar.robot.shm.PluginShmManager>`
  - ```{autodoc2-docstring} ros_sugar.robot.shm.PluginShmManager
    :summary:
    ```
````

### Functions

````{list-table}
:class: autosummary longtable
:align: left

* - {py:obj}`segment_name_base <ros_sugar.robot.shm.segment_name_base>`
  - ```{autodoc2-docstring} ros_sugar.robot.shm.segment_name_base
    :summary:
    ```
````

### API

````{py:function} segment_name_base(launcher_pid: int, plugin_id: str, feedback_key: str) -> str
:canonical: ros_sugar.robot.shm.segment_name_base

```{autodoc2-docstring} ros_sugar.robot.shm.segment_name_base
```
````

`````{py:class} ShmDescriptor
:canonical: ros_sugar.robot.shm.ShmDescriptor

```{autodoc2-docstring} ros_sugar.robot.shm.ShmDescriptor
```

````{py:method} pack() -> bytes
:canonical: ros_sugar.robot.shm.ShmDescriptor.pack

```{autodoc2-docstring} ros_sugar.robot.shm.ShmDescriptor.pack
```

````

`````

`````{py:class} ShmRingWriter(name_base: str, slot_count: int = DEFAULT_SLOT_COUNT, min_slot_size: int = DEFAULT_MIN_SLOT_SIZE)
:canonical: ros_sugar.robot.shm.ShmRingWriter

```{autodoc2-docstring} ros_sugar.robot.shm.ShmRingWriter
```

````{py:method} write(buffer) -> ros_sugar.robot.shm.ShmDescriptor
:canonical: ros_sugar.robot.shm.ShmRingWriter.write

```{autodoc2-docstring} ros_sugar.robot.shm.ShmRingWriter.write
```

````

````{py:method} close() -> None
:canonical: ros_sugar.robot.shm.ShmRingWriter.close

```{autodoc2-docstring} ros_sugar.robot.shm.ShmRingWriter.close
```

````

`````

`````{py:class} ShmReaderCache(retries: int = _READ_RETRIES)
:canonical: ros_sugar.robot.shm.ShmReaderCache

```{autodoc2-docstring} ros_sugar.robot.shm.ShmReaderCache
```

````{py:method} read(desc: ros_sugar.robot.shm.ShmDescriptor) -> typing.Optional[bytes]
:canonical: ros_sugar.robot.shm.ShmReaderCache.read

```{autodoc2-docstring} ros_sugar.robot.shm.ShmReaderCache.read
```

````

````{py:method} close() -> None
:canonical: ros_sugar.robot.shm.ShmReaderCache.close

```{autodoc2-docstring} ros_sugar.robot.shm.ShmReaderCache.close
```

````

`````

`````{py:class} PluginShmManager(launcher_pid: typing.Optional[int] = None, slot_count: int = DEFAULT_SLOT_COUNT, min_slot_size: int = DEFAULT_MIN_SLOT_SIZE)
:canonical: ros_sugar.robot.shm.PluginShmManager

```{autodoc2-docstring} ros_sugar.robot.shm.PluginShmManager
```

````{py:method} writer_for(plugin_id: str, feedback_key: str) -> ros_sugar.robot.shm.ShmRingWriter
:canonical: ros_sugar.robot.shm.PluginShmManager.writer_for

```{autodoc2-docstring} ros_sugar.robot.shm.PluginShmManager.writer_for
```

````

````{py:method} close() -> None
:canonical: ros_sugar.robot.shm.PluginShmManager.close

```{autodoc2-docstring} ros_sugar.robot.shm.PluginShmManager.close
```

````

`````