Environment Variable

Use the syntax $ENV{VAR} to read environment variable VAR.

https://cmake.org/cmake/help/latest/variable/ENV.html

Example usage

SET(CMAKE_C_COMPILER   $ENV{C_COMPILER_PATH_ANDROID})

set(my_var "ANDROID_ARCH=$ENV{ANDROID_ARCH}")

To Verify existence

Verify Existence

Verify environment variables are set:

if(NOT DEFINED ENV{C_COMPILER_PATH_ANDROID})
    message(FATAL_ERROR "You must set C_COMPILER_PATH_ANDROID environment variable")
endif()

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