LabStreamingLayer

https://labstreaminglayer.readthedocs.io/
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### Build and Install Project (Commandline)

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/app_build.rst.txt

Start the build process and install the application using CMake from the command line. This command builds the project and installs it to the specified CMAKE_INSTALL_PREFIX.

```bash
cmake --build . --config Release --target install
```

--------------------------------

### Installed Directory Tree Example

Source: https://labstreaminglayer.readthedocs.io/dev/build_full_tree.html

Example structure of the 'installed' directory after building and installing LabStreamingLayer, showing executables, libraries, and configuration files.

```tree
├── AppX
│   ├── AppX.exe
│   ├── liblsl64.dll
│   ├── Qt5Xml.dll
│   ├── Qt5Gui.dll
│   └── AppX_configuration.ini
├── AppY
│   ├── AppY.exe
│   ├── AppY_conf.exe
│   ├── liblsl64.dll
│   └── example.png
├── examples
│   ├── CppReceive.exe
│   ├── CppSendRand.exe
│   ├── SendDataC.exe
│   ├── liblsl64.dll
└── LSL
  ├── share
  │   ├── LSL
  │   │   ├── LSLCMake.cmake
  │   │   ├── LSLConfig.cmake
  │   │   └── LSLCMake.cmake
  ├── include
  │   ├── lsl_c.h
  │   └── lsl_cpp.h
  └── lib
    ├── liblsl64.dll
    ├── liblsl64.lib
    └── lslboost.lib

```

--------------------------------

### Example installed directory tree

Source: https://labstreaminglayer.readthedocs.io/dev/app_build.html

Visual representation of the expected file structure after a successful build and installation.

```text
├── AppX
│   ├── AppX.exe
│   ├── liblsl64.dll
│   ├── Qt5Xml.dll
│   ├── Qt5Gui.dll
│   ├── VendorDevice.dll
│   └── AppX_configuration.ini
└── LSL
  ├── share
  │   ├── LSL
  │   │   ├── LSLCMake.cmake
  │   │   ├── LSLConfig.cmake
  │   │   └── LSLCMake.cmake
  ├── include
  │   ├── lsl_c.h
  │   └── lsl_cpp.h
  └── lib
    ├── liblsl64.dll
    ├── liblsl64.lib
    └── lslboost.lib
```

--------------------------------

### Installed Directory Tree Example

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_full_tree.rst.txt

Illustrates the typical directory structure of an installed LabStreamingLayer distribution.

```bash
â”œâ”€â”€ AppX
â”‚   â”œâ”€â”€ AppX.exe
â”‚   â”œâ”€â”€ liblsl64.dll
â”‚   â”œâ”€â”€ Qt5Xml.dll
â”‚   â”œâ”€â”€ Qt5Gui.dll
â”‚   â””â”€â”€ AppX_configuration.ini
â”œâ”€â”€ AppY
â”‚   â”œâ”€â”€ AppY.exe
â”‚   â”œâ”€â”€ AppY_conf.exe
â”‚   â”œâ”€â”€ liblsl64.dll
â”‚   â””â”€â”€ example.png
â”œâ”€â”€ examples
â”‚   â”œâ”€â”€ CppReceive.exe
â”‚   â”œâ”€â”€ CppSendRand.exe
â”‚   â”œâ”€â”€ SendDataC.exe
â”‚   â”œâ”€â”€ liblsl64.dll
â””â”€â”€ LSL
  â”œâ”€â”€ share
â”‚   â”œâ”€â”€ LSL
â”‚   â”‚   â”œâ”€â”€ LSLCMake.cmake
```

--------------------------------

### Installed Directory Tree Example

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/app_build.rst.txt

This structure represents the typical output of an LSL application build, showing the executable, libraries, and configuration files.

```bash
     ├── AppX
     │   ├── AppX.exe
     │   ├── liblsl64.dll
     │   ├── Qt5Xml.dll
     │   ├── Qt5Gui.dll
     │   ├── VendorDevice.dll
     │   └── AppX_configuration.ini
     └── LSL
       ├── share
       │   ├── LSL
       │   │   ├── LSLCMake.cmake
       │   │   ├── LSLConfig.cmake
       │   │   └── LSLCMake.cmake
       ├── include
       │   ├── lsl_c.h
       │   └── lsl_cpp.h
       └── lib
         ├── liblsl64.dll
         ├── liblsl64.lib
         └── lslboost.lib
```

--------------------------------

### Run Basic LSL Plotter Example

Source: https://labstreaminglayer.readthedocs.io/_sources/info/viewers.rst.txt

This command runs a basic visualizer included with the Python bindings for LSL. Ensure pylsl and pyqtgraph are installed.

```bash
python -m pylsl.examples.ReceiveAndPlot
```

--------------------------------

### Build the liblsl install target

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/lib_dev.rst.txt

Compile the library and install it to the specified directory using the command line.

```bash
cmake --build build -j --config Release --target install
```

--------------------------------

### Import Visual Studio configuration

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_env.rst.txt

Use this JSON configuration file to import a minimal Visual Studio installation via the installer.

```json
{
    "version": "1.0",
    "components": [
        "microsoft.visualstudio.component.vc.coreide",
        "microsoft.visualstudio.component.vc.cmake.project"
    ]
}
```

--------------------------------

### Set CMake Install Prefix

Source: https://labstreaminglayer.readthedocs.io/dev/app_build.html

Specifies the directory where the built project will be installed. Use 'build/install' as a good default.

```cmake
-DCMAKE_INSTALL_PREFIX="build/install"
```

--------------------------------

### MATLAB LSL String Marker Examples

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/examples.rst.txt

Examples for sending and receiving irregular string-formatted streams in MATLAB.

```text
https://github.com/labstreaminglayer/liblsl-Matlab/tree/master/examples/SendStringMarkers.m
```

```text
https://github.com/labstreaminglayer/liblsl-Matlab/tree/master/examples/ReceiveStringMarkers.m
```

--------------------------------

### Launch MATLAB Visualization Tools

Source: https://labstreaminglayer.readthedocs.io/_sources/info/matlab_example_with_muse.rst.txt

Commands to start stream visualization within the MATLAB environment.

```matlab
vis_stream
```

```matlab
bcilab
```

```matlab
eeglab
```

--------------------------------

### Configure CMake for Mac Build

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_full_tree.rst.txt

Example command for building LSL on macOS using Homebrew-installed Qt.

```bash
cmake .. -DQt5_DIR=$(brew --prefix qt)/lib/cmake/Qt5/ -DLSLAPPS_LabRecorder=ON -DLSLAPPS_Benchmarks=ON -DLSLAPPS_XDFBrowser=ON
```

--------------------------------

### Python LSL String Marker Examples

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/examples.rst.txt

Examples for sending and receiving irregular string-formatted streams, typically used for event markers.

```text
https://github.com/labstreaminglayer/liblsl-Python/tree/master/pylsl/examples/SendStringMarkers.py
```

```text
https://github.com/labstreaminglayer/liblsl-Python/tree/master/pylsl/examples/ReceiveStringMarkers.py
```

--------------------------------

### Python SendData Example

Source: https://labstreaminglayer.readthedocs.io/info/network-connectivity.html

This example demonstrates how to send data using pylsl. Ensure the SendData.py script is modified to print received data to a file or console for testing.

```python
https://github.com/chkothe/pylsl/blob/master/examples/SendData.py
```

--------------------------------

### Python ReceiveData Example

Source: https://labstreaminglayer.readthedocs.io/info/network-connectivity.html

This example demonstrates how to receive data using pylsl. Ensure the ReceiveData.py script is modified to print received data to a file or console for testing.

```python
https://github.com/chkothe/pylsl/blob/master/examples/ReceiveData.py
```

--------------------------------

### Configure CMake for Windows Build

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_full_tree.rst.txt

Example command for building LSL on Windows using Visual Studio 14 2015 with specific Qt and Boost paths.

```bash
cmake .. -G "Visual Studio 14 2015 Win64" -DQt5_DIR=C:\Qt\5.11.1\msvc2015_64\lib\cmake\Qt5 -DBOOST_ROOT=C:\local\boost_1_67_0 -DLSLAPPS_LabRecorder=ON -DLSLAPPS_XDFBrowser=ON -DLSLAPPS_OpenVR=ON
```

--------------------------------

### More Specific Stream Query Examples

Source: https://labstreaminglayer.readthedocs.io/info/faqs.html

Use more specific queries to resolve a single stream when multiple matches are found. Examples include specifying the stream name, hostname, or serial number.

```text
name='Cognionics Quick-20'
```

```text
name='Cognionics Quick-20' and hostname='My-PC001'
```

```text
type='EEG' and serial_number='ABCDEF'
```

--------------------------------

### Configure Project with CMake (Commandline)

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/app_build.rst.txt

Configure the project using CMake from the command line, specifying the source directory, build directory, build type, and installation prefix. This is a recommended option for command-line users.

```bash
cmake -S . -B build -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX="build/install" {other options}
```

--------------------------------

### GET /samples_available

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/inlet.html

Query whether samples are currently available for immediate pickup.

```APIDOC
## GET /samples_available

### Description
Query whether samples are currently available for immediate pickup. Note that this should not be used to determine if a pull call will block.

### Method
GET

### Response
#### Success Response (200)
- **value** (std::size_t) - The number of samples available (or 1/0 if exact count is unsupported).
```

--------------------------------

### Build Project Using CMake Build System

Source: https://labstreaminglayer.readthedocs.io/dev/cmake.html

After a build folder is configured, binaries can be built using CMake's build system wrapper. This command builds the project, specifies the Release configuration, uses parallel jobs, and targets the 'install' step.

```bash
cmake --build path/to/build/folder --config Release -j --target install
```

--------------------------------

### Clean build directory

Source: https://labstreaminglayer.readthedocs.io/dev/app_build.html

Commands to remove an existing build directory before starting a fresh build.

```shell
rmdir /S build
```

```shell
rm -Rf build
```

--------------------------------

### Set LD_LIBRARY_PATH for Qt

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_env.rst.txt

Update the environment variable to include the path to the Qt library directory. Replace {version} with the specific Qt version installed.

```bash
LD_LIBRARY_PATH="$LD_LIBRARY_PATH:/opt/Qt/{version}/gcc_64/lib"
```

--------------------------------

### Configure CMake Variables in Visual Studio

Source: https://labstreaminglayer.readthedocs.io/dev/app_build.html

Example of how to set CMake variables like Qt5_DIR, BOOST_ROOT, Vendor_ROOT, and LSL_INSTALL_ROOT within a Visual Studio CMakeSettings.json file for a specific configuration.

```json
,
      "variables": [
        {
          "name": "Qt5_DIR",
          "value": "C:\\Qt\\5.11.1\\msvc2015_64\\lib\\cmake\\Qt5 "
        },
        {
          "name": "BOOST_ROOT",
          "value": "C:\\local\\boost_1_67_0"
        },
        {
          "name": "Vendor_ROOT",
          "value": "C:\\path\\to\\vendor\\sdk"
        },
        {
          "name": "LSL_INSTALL_ROOT",
          "value": "C:\\path\\to\\liblsl\\install"
        }
      ]

```

--------------------------------

### Initialize Muse Stream with muse-io

Source: https://labstreaminglayer.readthedocs.io/_sources/info/matlab_example_with_muse.rst.txt

Connect the Muse headset to the local network via LSL using the muse-io utility.

```bash
muse-io --device Muse-XXXX --lsl-eeg EEG
```

--------------------------------

### Set LSL Install Root for CMake

Source: https://labstreaminglayer.readthedocs.io/dev/app_build.html

Specifies the installation root for liblsl. This is often not required if liblsl is installed via package managers or is in a sibling directory.

```cmake
-DLSL_INSTALL_ROOT=path/to/liblsl/
```

--------------------------------

### Build Documentation Locally

Source: https://labstreaminglayer.readthedocs.io/dev/doc_syntax.html

Commands to generate documentation locally using Sphinx.

```bash
make html
```

```bash
sphinx-build . _build
```

--------------------------------

### Clone repository with submodules

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/full_tree.rst.txt

Initial command to clone the repository and initialize all submodules.

```bash
git clone --recurse-submodules git@github.com:labstreaminglayer/labstreaminglayer.git
```

--------------------------------

### Configure Project with CMake GUI

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/app_build.rst.txt

Initiate the CMake configuration process using the GUI, specifying source and build directories. This method allows for interactive setting of options and paths.

```bash
cmake-gui -S . -B build
```

--------------------------------

### Initialize and update a single submodule

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/full_tree.rst.txt

Command to fetch and check out a specific submodule.

```bash
git submodule update --init <path>
```

--------------------------------

### GET lsl_local_clock

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/freefuncs.html

Obtain a local system time stamp in seconds.

```APIDOC
## GET lsl_local_clock

### Description
Obtain a local system time stamp in seconds. The resolution is better than a millisecond.

### Response
- **return** (double) - The local system time stamp in seconds.
```

--------------------------------

### Configure and Build Project with CMake

Source: https://labstreaminglayer.readthedocs.io/dev/cmake.html

This command configures a project, specifying the source and build directories, enabling unit tests, and using the Ninja generator.

```bash
cmake -S . -B build -DLSL_UNITTESTS=1 -G Ninja
```

--------------------------------

### GET /stream_inlet/time_correction

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/inlet.html

Retrieves an estimated time correction offset for the given stream.

```APIDOC
## GET /stream_inlet/time_correction

### Description
Retrieve an estimated time correction offset for the given stream to map remote timestamps to the local clock domain.

### Parameters
#### Query Parameters
- **timeout** (double) - Optional - Timeout to acquire the first estimate (default: FOREVER).

### Response
#### Success Response (200)
- **offset** (double) - The time correction estimate.
```

--------------------------------

### GET lsl_time_correction_ex

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/freefuncs.html

Retrieve an estimated time correction offset for a given stream.

```APIDOC
## GET lsl_time_correction_ex

### Description
Retrieve an estimated time correction offset for the given stream. This value should be added to a remotely generated time stamp to map it into the local clock domain.

### Parameters
#### Path Parameters
- **in** (lsl_inlet) - Required - The lsl_inlet object to act on.
- **timeout** (double) - Required - Timeout to acquire the first time-correction estimate.

### Response
#### Success Response (200)
- **return** (double) - The time correction estimate.
- **remote_time** (double) - The current time of the remote computer.
- **uncertainty** (double) - The maximum uncertainty of the given time correction.
- **ec** (int32_t) - Error code: nonzero if lsl_timeout_error or lsl_lost_error occurs.
```

--------------------------------

### Find liblsl with CMake

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/app_dev.rst.txt

Use this configuration in your CMakeLists.txt to locate the liblsl library installation.

```cmake
find_package(LSL 1.13.0 REQUIRED
	HINTS ${LSL_INSTALL_ROOT}
	"${CMAKE_CURRENT_LIST_DIR}/../../LSL/liblsl/build/"
	"${CMAKE_CURRENT_LIST_DIR}/../../LSL/liblsl/build/install"
	PATH_SUFFIXES share/LSL
)
```

--------------------------------

### Configure Git settings

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/full_tree.rst.txt

Recommended settings to manage submodules and commit history effectively.

```bash
git config --add setting.name value
```

```bash
git config --global --add ...
```

--------------------------------

### GET /was_clock_reset

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/inlet.html

Query whether the clock was potentially reset since the last call.

```APIDOC
## GET /was_clock_reset

### Description
Query whether the clock was potentially reset since the last call to was_clock_reset(). Useful for applications estimating precise clock drift.

### Method
GET

### Response
#### Success Response (200)
- **result** (bool) - True if the clock was reset.
```

--------------------------------

### GET /stream_inlet/info

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/inlet.html

Retrieves the complete information of the given stream, including the extended description.

```APIDOC
## GET /stream_inlet/info

### Description
Retrieve the complete information of the given stream, including the extended description.

### Parameters
#### Query Parameters
- **timeout** (double) - Optional - Timeout of the operation (default: FOREVER).

### Response
#### Success Response (200)
- **info** (stream_info) - The complete stream information.
```

--------------------------------

### LSL Configuration File Reference

Source: https://labstreaminglayer.readthedocs.io/info/lslapicfg.html

Default configuration settings for LSL timing, buffering, and logging.

```ini
; This setting offers fine control over various intervals and constants in LSL.
; We apologize that there is not more documentation for these settings at this time.
; Brief descriptions can be found in https://github.com/sccn/liblsl/blob/master/src/api_config.h#L149-L200
; UseProtocolVersion = not set, read from common.h.
WatchdogCheckInterval = 15.0
WatchdogTimeThreshold = 15.0
MulticastMinRTT = 0.5
MulticastMaxRTT = 3.0
UnicastMinRTT = 0.75
UnicastMaxRTT = 5.0
ContinuousResolveInterval = 0.5
TimerResolution = 1
MaxCachedQueries = 100
TimeUpdateInterval = 2.0
TimeUpdateMinProbes = 6
TimeProbeCount = 8
TimeProbeInterval = 0.064
TimeProbeMaxRTT = 0.128
OutletBufferReserveMs = 5000
OutletBufferReserveSamples = 128
SendSocketBufferSize = 0
InletBufferReserveMs = 5000
InletBufferReserveSamples = 128
ReceiveSocketBufferSize = 0
SmoothingHalftime = 90.0
ForceDefaultTimestamps = false

[log]
; the log level. Only messages at this level or below will be logged
; -2: errors
; -1: warnings
; 0: information
; 1-9: increasingly less important details
; When liblsl is built with LSL_DEBUGLOG=On, the levels 1-9 will log more details
; The log looks like this:
; Date and time          |  runtime  |  thread ID        | source location        | level | Log message
; 2020-11-11 08:54:08.696 (   3.132s) [        A5247740]   inlet_connection.cpp:46    WARN| The stream named 'timesync' can't be recovered automatically if its provider crashes because it doesn't have a unique source ID
level = -2
; liblsl can also write all log messages to a file specified here. By default, log messages will be appended
file =
```

--------------------------------

### GET /pull_chunk_numeric_structs

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/inlet.html

Methods to pull chunks of samples from the inlet, with options for timestamps or data-only retrieval.

```APIDOC
## GET /pull_chunk_numeric_structs

### Description
Pull a chunk of samples from the inlet. Multiple overloads exist for returning data with timestamps, only the most recent timestamp, or data only.

### Method
GET

### Parameters
#### Request Body
- **chunk** (vector of C-style structs) - Required - A vector to hold the samples.
- **timestamps** (vector) - Optional - A vector to hold the time stamps (only for the full version).

### Response
#### Success Response (200)
- **Return** (bool/double/vector) - Returns true if data obtained, the most recent timestamp, or a vector of samples.

### Exceptions
- **lost_error** - Thrown if the stream source has been lost.
```

--------------------------------

### Display liblsl folder structure

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/lib_dev.rst.txt

The expected directory layout after cloning the repository.

```bash
     (working directory)
     └── liblsl
         ├── {...}
         ├── include
         ├── lslboost
         ├── project
         ├── src
         └── testing
```

--------------------------------

### Push Sample as Raw Pointer

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/outlet.html

Pushes a pointer to values as a sample into the outlet. This is a lower-level function for existing buffers. Ensure the buffer size is sufficient.

```cpp
void push_sample(_const_ float *_data_, double _timestamp_ = 0.0, bool _pushthrough_ = true)
```

--------------------------------

### Java LSL Chunked Data Transmission

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/examples.rst.txt

Examples for transmitting data in chunks for improved convenience in Java.

```text
https://github.com/labstreaminglayer/liblsl-Java/tree/master/src/examples/SendDataInChunks.java
```

```text
https://github.com/labstreaminglayer/liblsl-Java/tree/master/src/examples/ReceiveDataInChunks.java
```

--------------------------------

### Configure local.properties

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_android.rst.txt

Set the paths for NDK, SDK, and CMake in the local.properties file.

```properties
ndk.dir=C\:\Users\user\AppData\Local\Android\Sdk\ndk\16.1.4479499
android.ndkVersion=16.1.4479499
sdk.dir=C\:\Users\user\AppData\Local\Android\Sdk
cmake.dir=C\:\Program Files\CMake
```

--------------------------------

### Handle Stream Meta-Data in LSL

Source: https://labstreaminglayer.readthedocs.io/dev/examples.html

Shows how to attach and read meta-data for LSL streams. Meta-data makes streams self-describing.

```c
#include <lsl_cpp.h>
#include <iostream>
#include <vector>

int main() {
    // Create a stream with meta-data
    lsl::stream_info info("MetaStream", "EEG", 8, 0.0, "cf", "EEG_Data_With_Meta");
    lsl::xml_element channels = info.desc().append_child("channels");
    for (int i = 0; i < 8; ++i) {
        channels.append_child("channel")
            .append_child_value("label", "EEG " + std::to_string(i + 1))
            .append_child_value("unit", "microvolts")
            .append_child_value("type", "EEG");
    }
    lsl::stream_outlet outlet(info);

    // Resolve the stream and read its meta-data
    std::vector<lsl::stream_info> results = lsl::resolve_streams("name=\"MetaStream\"");
    if (!results.empty()) {
        lsl::stream_inlet inlet(results[0]);
        lsl::xml_element desc = inlet.info().desc();
        std::cout << "Stream Description:" << std::endl;
        std::cout << desc.first_child().name() << std::endl; // Should be 'channels'
        for (lsl::xml_element channel : desc.child("channels").children("channel")) {
            std::cout << "  Label: " << channel.child_value("label") << ", Unit: " << channel.child_value("unit") << std::endl;
        }
    }

    return 0;
}
```

--------------------------------

### GET Library and Protocol Info

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/freefuncs.html

Functions to retrieve library version, library info, and protocol version.

```APIDOC
## GET lsl_library_version
### Description
Returns the version of the liblsl library.

## GET lsl_library_info
### Description
Returns a string containing library information for debugging purposes.

## GET lsl_protocol_version
### Description
Returns the protocol version. Clients with different major versions are incompatible.
```

--------------------------------

### Build liblsl with Gradle

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_android.rst.txt

Execute the build process to generate the AAR file.

```bash
gradlew assembleRelease
```

--------------------------------

### MATLAB LSL Chunked Data Transmission

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/examples.rst.txt

Examples for transmitting data in chunks to improve performance in the MATLAB interpreter.

```text
https://github.com/labstreaminglayer/liblsl-Matlab/tree/master/examples/SendDataInChunks.m
```

```text
https://github.com/labstreaminglayer/liblsl-Matlab/tree/master/examples/ReceiveDataInChunks.m
```

--------------------------------

### LSL Utility Functions

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/genindex.html

Provides essential utility functions for LSL, such as getting library information and time correction.

```APIDOC
## LSL Utility Functions

### Description
Core functions for interacting with the LSL library.

### Functions
- `lsl_library_info()`: Returns information about the LSL library.
- `lsl_library_version()`: Returns the version of the LSL library.
- `lsl_local_clock()`: Returns the current local system time.
- `lsl_protocol_version()`: Returns the current LSL protocol version.
- `lsl_time_correction_ex(double)`: Returns the time correction offset for a given timestamp.
```

--------------------------------

### Retrieve liblsl Repository

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/build_android.rst.txt

Clone the labstreaminglayer repository and initialize the necessary submodules.

```bash
git clone --depth=1 https://github.com/sccn/labstreaminglayer.git
git submodule update --init LSL/liblsl LSL/liblsl-Java
```

--------------------------------

### Configure LSL_INSTALL_ROOT in CMake

Source: https://labstreaminglayer.readthedocs.io/dev/LSL_INSTALL_ROOT.html

Set the absolute path to the installed LSL directory or update the CMAKE_MODULE_PATH to include the cmake subfolder.

```cmake
-DLSL_INSTALL_ROOT=C:/LSL/build/install/
```

```cmake
list(APPEND CMAKE_MODULE_PATH "C:/path/to/LSL/build/install/cmake/")
```

--------------------------------

### Configure Universal Executable on Windows

Source: https://labstreaminglayer.readthedocs.io/dev/app_build.html

Builds a more universal executable on Windows. Ensure the toolset and host architecture are correctly specified.

```cmake
-T v142,host=x86
```

--------------------------------

### Querying stream information with XPath

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/streaminfo.html

Examples of XPath query strings used with the matches_query method to filter stream information.

```text
channel_count>5 and type='EEG'
type='TestStream' or contains(name,'Brain')
name='ExampleStream'
```

--------------------------------

### MATLAB LSL Numeric Data Transmission

Source: https://labstreaminglayer.readthedocs.io/_sources/dev/examples.rst.txt

Basic examples for sending and receiving multi-channel numeric time series data.

```text
https://github.com/labstreaminglayer/liblsl-Matlab/tree/master/examples/SendData.m
```

```text
https://github.com/labstreaminglayer/liblsl-Matlab/tree/master/examples/ReceiveData.m
```

--------------------------------

### Push Sample as C Array

Source: https://labstreaminglayer.readthedocs.io/projects/liblsl/ref/outlet.html

Pushes a C array of values as a sample into the outlet. Handles type checking and conversion. Use for fixed-size numeric data.

```cpp
template<class T, int32_t N>
void push_sample(_const_ T _data_[_N_], double _timestamp_ = 0.0, bool _pushthrough_ = true)
```
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