Complex sentence: Some can be grafted to the appropriate Linux system calls, or partially reuse the code from corresponding Linux system calls, and the remnants have no counterpart in Linux require to use low-level Linux kernel functions to implement.
Split into simpler sentences: Some can be grafted to the appropriate Linux system calls, or partially reuse the code from corresponding Linux system calls. The remnants have no counterpart in Linux and require to use low-level Linux kernel functions to implement.