How to unlock all API s

At the beginning - Тhere is nowhere a license how to use the Azure Sphere, only recommendations.

and This is not hack ... ( maybe little )

Can work with Visual Studio SDK and with this project ( VSCode + PlatformIO )

Tested with last sysroot 19.05

Demo ( used wolfSSL ) MQTT to Amazon, Google

BaseAPI information

Significant portions of the following C standard library features are excluded:

• file system paths (why not)
• terminal support (not need, for the most part FS is read only)
• ioctl and fcntl functions (need)
• authentication and authorization (!?)
• syscall functions
• System V

So, what we know - Azure Sphere is built in large part by Open Source tools and libraries:

• GCC ( arm-poky-linux-musleabi )
• Linux Kernel 4.x
• musl libc
• libcurl
• wolfSSL
• Azure IoT C SDKs and Libraries

What is missing - configurations and header files - explore github with upper links and follow the logic