TP 4.2.1 Release Notes

  • Article

Technical Preview 4.2.1 (August, 2018) includes the changes and known issues described in this article.

New features and changes

In addition to various usability enhancements, this Technical Preview release includes the changes described below.

Curl support

Curl support has been modified in the following ways:

  • Functions that the underlying Azure Sphere OS does not support have been removed, such as those that require writable files (cookies) or operate on UNIX sockets.

  • Additional functions, such as the mprintf() family, have also been removed because they will not be supported in future libcurl releases.

  • Server authentication is now supported, so that applications can now verify that they are communicating with the expected server. The server's certificate must be signed by a Certificate Authority (CA) that the device trusts. Several CAs are built into the Azure Sphere device. In addition, you can add a certificate to your application image package.

Clients should use existing curl mechanisms such as curl_version_info or checking the return code from curl_easy_setopt to determine whether a particular feature is supported.

Device update status

The azsphere.exe command-line utility now includes the azsphere device show-ota-status command, which returns information about which version of the Azure Sphere OS your device is running and whether an OS update is available or being downloaded.

Known issues

The following are known issues in this Technical Preview release.

Development language

The Azure Sphere SDK supports application development only in C.

Currently, the Visual Studio Integrated Development Environment (IDE) does not generate an error if you add a C++ source file to an Azure Sphere project. However, C++ development is not supported, and the resulting project will not build correctly.

Status LEDs

The application status and Wi-Fi status LEDs on the MT3620 Reference Board are provided for customer application use. The system software does not control these LEDs automatically.