Reading one file before moving 3 other related files

Hi all,

I am actually working on SAP PO 7.4.

I have scenario where I need to move 4 files based on the content of the first file (using FTPs adapter).

First instance, I have 4 files with identical names on a server among hundreds, just the extension that is different :

file_date_time.xx

file_date_time.yy

file_date_time.cc

file_date_time.ii

file_date_time2.xx

file_date_time2.yy

file_date_time2.cc

file_date_time2.ii

.....

.....

In my scenario, I always need to read file_date_time.yy first as its content allows me to know where to route all 3 others related messages.

My issue is : How can I tell PI to pick only these 3 others files based on the content of the first file I have read ?

Hope I was clear.

Thank you in advance for answers.

Jean-Philippe