QYAPSOL api and filter data problem - GUI0141 error code

hi,

i'm trying to use the QYAPSOL api but i always get GUI0141 in the errorcode - 
Filter specification is not valid.

DapiRetrieveDisk  PR                  EXTPGM('QYASPOL')                  D  
receiver                  32000A
D  length                       10I 0 CONST
D  listInfo                     80A 
D  recToReturn                  10I 0 CONST     
D  filters                      10I 0 CONST        
D  filterInfo                  100A   CONST       
D  formatName                    8A   CONST  
D  errorCode                   200A            

DFilterData       DS                  QUALIFIED      
D  data                         16A           
D  overallSize                  10I 0 OVERLAY(data:1)         
D  filterKey                    10I 0 OVERLAY(data:5)        
D  dataSize                     10I 0 OVERLAY(data:9)             
D  filterData                   10I 0 OVERLAY(data:13) 

<some free code>

FilterData.filterKey = 1;    
FilterData.filterData = -1;           
FilterData.dataSize = 16;     
FilterData.overallSize = %size(FilterData.data);   

apiRetrieveDisk(receiver        :                                               
        %len(receiver)  :   
                listInfo        :                  
                -1              :             
                0               :             
                FilterData.data :             
                listFormat      :             
                errorcode      );  
</some free code>

why is working with os400 api always so difficult.

can someone pleeeeaaasssee help me.

thanx in advance

mihael knezevic

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