# fsVarsCustomSimVarSet<no value>

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Deprecated. Use `fsVarsIVarSet, `[fsVarsOVarSet](fsvarsovarset/)` or `[fsVarsZVarSet](fsvarszvarset/)instead.

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The **fsVarsCustomSimVarSet** function can be used to set the value of a specific CustomSImVar.

 

##### Syntax

``` wasm
FsVarError fsVarsCustomSimVarSet(
    FsCustomSimVarId varId,
    FsUnitId unitId,
    double value
);
```

 

##### Parameters

{{< table-wrapper >}}

| Parameters | Description                                                             |
|------------|-------------------------------------------------------------------------|
| `varId`    | The ID of a custom simvar.                                              |
| `unitId`   | The ID of an unit (found using [fsVarsGetUnitId](fsvarsgetunitid/)). |
| `value`    | The new value of the simvar.                                            |

{{< /table-wrapper >}}


 

##### Return Values

The function returns a `FsVarError`, 0 means there is no error.

 

##### Example

``` wasm
FsUnitId unitId = fsVarsGetUnitId("DEGREES");
FsCustomSimVarId varId = fsVarsRegisterCustomSimVar("TOTO", nullptr, FsSimCustomSimVarScopeSim);
double newValue = 123;
if (fsVarsCustomSimVarSet(varId , unitId, newValue) == FS_VAR_ERROR_NONE)
{
    // valid
}
else
{
    // error
}
```