[CMake] finding if feature is supported by host

[Vania Joloboff]

Hi

I can find if an include file exists with CHECK_INCLUDE_FILE
But I want to know if a particular feature is supported
in our case we need to know if the mmap call exists
and whether it supports the MAP_ANONYMOUS feature
With autoconf, I can use AC_TRY_COMPILE to try compiling
a program using the feature.
Is there some equivalent in cmake ?

Or I have to build my own TRY_COMPILE command to check if a feature
is supported by a particular function call ?

Thanks