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**DLL( **[** **//flag//** **]** )**

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| **DLL** | Declares a PROCEDURE defined externally in a .DLL. |
| //flag// | A numeric constant, equate, or Project system define which specifies the attribute as active or not. If the //flag// is zero, the attribute is not active, just as if it were not present. If the //flag// is any value other than zero, the attribute is active. Uniquely, it may be an undefined label, in which case the attribute is active. |

The **DLL** attribute specifies that the PROCEDURE on whose prototype it is placed is defined in a .DLL. The DLL attribute is required for 32-bit applications because .DLLs are relocatable in a 32-bit flat address space, which requires one extra dereference by the compiler to address the procedure.

**Example:**

** MAP**

**  MODULE('STDFuncs.DLL')            !A standard functions .DLL**

**Func50 PROCEDURE(SREAL),REAL,PASCAL,****DLL****(dll_mode) !**

**  END**

** END**

**See Also:**

[[external  set defined externally .htm|EXTERNAL]]