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**BeginUnique( **//applicationname //**//)//**

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| **BeginUnique** | Sets an application to run as a single process |
| //applicationname// | A string constant or variable that specifies name of your application. Example: 'INVOICE.EXE' |

**BeginUnique** returns FALSE if the program specified in //applicationname //is already running (active). If not running, **BeginUnique** returns an event number specified by Windows. This event number can be used by the **EndUnique** statement to terminate the single process mode.

To add this function to your existing applications, you need only include the CWUTIL.INC file in the Global Map section of your program:

**INCLUDE('CWUTIL.INC'),ONCE**

**Return Data Type:     **LONG

**Example:**

**IF NOT BeginUnique(GLO:ApplicationName)**

** MESSAGE(CLIP(GLO:ApplicationName) & ' already running.')**

** RETURN**

**ELSE**

** RUN(GLO:ApplicationName)**

**END**

**See Also:**

[[endunique close an application s event handle .htm|EndUnique]]