What is the Relationship ID to find employee line manger and his subordinate?

Dear Experts,

1.Can you suggest FM - where using particular employee Position ID can we pull out his line manger and subordinate and also provide the relationship code to get the detail of line manager and subordinate.

2.For eg say employee position ID -30000019 what input i should give in table HRP1001 to get his line manager & subordinate .

Regards

Vinodh