Figure 1

 -----------------------------------
 |  Your Application                |
 |  R ------------------------------
 |  I |  File Manager
 |  N |  R ---------------------
 |    |  I | OS/2  KERNEL       R
 |  3 |  N |   ---------------  I
 |    |  G |   | Device Driver  N
 |    |    |   ---------------  G
 |    |    |____________________O
 |    |  2
 |    -----------------------------
 |                                 |
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