unionfs_set_in_progress_flag
int unionfs_set_in_progress_flag(struct vnode *, unsigned int);
error = unionfs_set_in_progress_flag(vp, UNIONFS_COPY_IN_PROGRESS);
error = unionfs_set_in_progress_flag(vp, UNIONFS_COPY_IN_PROGRESS);
error = unionfs_set_in_progress_flag(vp, UNIONFS_COPY_IN_PROGRESS);
error = unionfs_set_in_progress_flag(dvp, UNIONFS_LOOKUP_IN_PROGRESS);