| 
 |  | 
              INT 21 - DOS 3.x - SET MEMORY ALLOCATION STRATEGY               
  
    
      | 
         Input  | 
      DOS1 | 
      N | 
      DOS2 | 
      N | 
      
         DOS3  | 
      Y | 
      DOS5 | 
      Y | 
      
         Output  | 
     
    
      | 
         AX  | 
      58h | 
      01h | 
      Error
        Code | 
      AX | 
     
    
      | 
         BX  | 
       Strategy
        Code | 
        | 
        | 
      BX | 
     
    
      | 
         CX  | 
        | 
        | 
        | 
        | 
      CX | 
     
    
      | 
         DX  | 
        | 
        | 
        | 
        | 
      DX | 
     
    
      | 
         ES:DI  | 
        | 
      Set
        if Error | 
      CF | 
     
   
 
Note:   The Set subfunction accepts any value in BL; 2 or greater
           means last fit. the Get subfunction returns the last value
           set, so programs should check whether the value is >= 2,
           not just equal to 2.
Strategy Codes: 00h = First Fit, low 640K
                01h = Best Fit, low 640K
                02h = Last Fit, low 640K
                40h = First Fit, UMBs Only
                41h = Best Fit, UMBs Only
                42h = Last Fit, UMBs Only
                80h = First Fit, UMBs First
                81h = Best Fit, UMBs First
                82h = Last Fit, UMBs First
 
See Also 48h 49h 4Ah Memory Control Block Error Codes |