Integraiton scenario to read SAP table

Hi,

I have a integration scenario where I get a message from legacy and needs to be written as file in ECC. The legacy file has two parts, the first part has 3 characters which I should use and read a table ( the custom table can be in XI or ECC) and get the file path and file name. After I get file path and file name I need to strip out the first part of the legacy message and map the second part of the message.

The mapped document should be written as a file in ECC using the file name and file path retrieved above ( i need to provide file name and file path in the channel). Can anyone help on how to achieve this?

Thanks in advance for your help.