Using real_parent is correct in all kernels if you are concerned with
anything like the parent of the process. The task_struct.parent field in
vanilla kernels in fact only really relates to ptrace.
In RHEL5 and F[678] kernels, the utrace patch removed the ptrace-related
parent field and renamed real_parent to parent. In future Fedora kernels,
there may or may not be a ptrace-related parent field, but the real useful
field will go back to being called real_parent (so as to minimize the
cosmetic divergence from upstream code). (No statements about RHEL5>.2
kernels at this time.)
Thanks,
Roland