perl -e print(pack('II',0x085c,0x5c080000)); > temp.pk
perl -e "print(pack('NN',map($_*2,unpack('II',<>))));" > temp2.bk
perl -e "printf('%8x:%8x',unpack('NN',<>));"  temp2.pk
produces -->     10b8:b8100000  (as expected)