Data Areas

I am writing a program that will read from a data area.  This data area will
be in one of several libraries, none of which will be in the job's library
list.

My experience with data areas is to define a UDS ex. for a 10 alpha data
area:

     D DMARTXDATE     UDS                  DTAARA
     D  ODREVDT                      10A

Then at runtime, the ODREVDT variable will contain the value from the data
area.  If I want to change it, I modify the ODREVDT variable, and do an OUT
operation:

     C                   OUT       DMARTXDATE

The problem with the new program is that the data area won't be in the
library list at runtime.  I need to resolve the library name at runtime,
then retrieve the contents of the data area, and proceed based on these
contents.  I don't want to make a CL/RPG pair.  I looked at the QWCRDTAA
API, but I wonder if this is really necessary for this task.  Can I
accomplish the task without using this API?

Thanks in advance.