How to trigger process code for inbound idoc (No transaction invoved)

Hi friends..

I have to select data from SAP and put it in internal table and then put that data in standard IDOC and standard process that idoc...there is no transaction involved..

its SAP to SAP Posting ie within same client using IDOC.

i have tested in WE19..its OK..

how shud i do coding and triggering of process code.