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# BitMaskRead

Performs a bitwise mask read operation.

## Method Signature

```
BitMaskRead(number=[long], start=[integer], length=[integer])
```

### Arguments

| Argument | Type      | Required | Description                                                             | Default |
| -------- | --------- | -------- | ----------------------------------------------------------------------- | ------- |
| `number` | `long`    | `true`   | 64-bit signed integer from which to read the mask.                      |         |
| `start`  | `integer` | `true`   | Start bit for the read mask (Integer in the range 0-31, inclusive).     |         |
| `length` | `integer` | `true`   | Length of bits in the read mask (Integer in the range 0-31, inclusive). |         |

## Examples

### Bitwise Mask Read

Uses the bitMaskRead function to read each of the corresponding bits specified in the mask

[Run Example](https://try.boxlang.io/?code=eJxLyizxTSzODkpNTNFQMNZRMNBRMFTQtOYCAGABBko%3D)

```java
bitMaskRead( 3, 0, 1 );

```

Result: 1

### Using non zero start parameter

Bit shift the mask 2 places

[Run Example](https://try.boxlang.io/?code=eJxLyizxTSzODkpNTNFQMDTQUTDSUTBU0LTmAgBmzAZ6)

```java
bitMaskRead( 10, 2, 1 );

```

Result: 0

### Using non zero read mask start and length parameters

[Run Example](https://try.boxlang.io/?code=eJxLyizxTSzODkpNTNFQMDTQUTDUUTBW0LTmAgBmzgZ7)

```java
bitMaskRead( 10, 1, 3 );

```

Result: 5

### Additional Examples

[Run Example](https://try.boxlang.io/?code=eJwrL8osSfUvLSkoLdFQSMos8U0szg5KTUzRUDAyNdVRACEFTQVNa65yZIVKNklFdkoYwpj6DXQUTCD6AeqjHy8%3D)

```java
writeOutput( bitMaskRead( 255, 5, 5 ) );
writeOutput( "<br>" );
writeOutput( bitMaskRead( 255, 0, 4 ) );

```

## Related

* [BinaryDecode](/boxlang-language/reference/built-in-functions/binary/binarydecode.md)
* [BinaryEncode](/boxlang-language/reference/built-in-functions/binary/binaryencode.md)
* [BitAnd](/boxlang-language/reference/built-in-functions/binary/bitand.md)
* [BitMaskClear](/boxlang-language/reference/built-in-functions/binary/bitmaskclear.md)
* [BitMaskSet](/boxlang-language/reference/built-in-functions/binary/bitmaskset.md)
* [BitNot](/boxlang-language/reference/built-in-functions/binary/bitnot.md)
* [BitOr](/boxlang-language/reference/built-in-functions/binary/bitor.md)
* [BitSh](/boxlang-language/reference/built-in-functions/binary/bitsh.md)
* [bitShln](/boxlang-language/reference/built-in-functions/binary/bitshln.md)
* [bitShrn](/boxlang-language/reference/built-in-functions/binary/bitshrn.md)
* [BitXor](/boxlang-language/reference/built-in-functions/binary/bitxor.md)


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