Function mmap 

pub fn mmap(
    address: usize,
    length: usize,
    protection: usize,
    flags: usize,
    fd: Fd<'_>,
    offset: usize,
) -> Result<*mut c_void, Error>

Map a memory object in to the processes address space.

Safety

Though creating a memory mapping can be considered safe, use of the memory mapping is likely quite unsafe. Extra care must be taken when using a shared memory mapping.