BITRESET

• Source: https://www.freebasic.net/wiki/wikka.php?wakka=KeyPgBitreset
• Last revised: 2020-06-16

---

Gets the value with a specified bit cleared, from a copied integer.

Syntax

` #define Bitreset( value, bit_number ) ((value) and not (Cast(TypeOf(Value), 1) shl (bit_number)))

`

Usage

` result = Bitreset( value, bit_number )

`

Parameters

value

The integer value.

bit_number

The index of the bit to clear.

Return Value

Returns the integer value with the specified bit cleared.

Description

This macro expands to a copy of the integer value with the specified bit_number cleared (to off, or 0). Behaves as value And Not (1 Shl bit_number).

To clear a specified bit in a variable, the following assignment can be used: variable = Bitreset( variable, bit_number )

The valid range of values for bit_number depends on the size, in bits, of Typeof(value), which is 0 (from the lowest bit) through Sizeof(value) * 8 - 1 (up to the highest bit). See Standard Datatype Limits for a table of the standard datatypes and their sizes.

For the bit_number values outside the valid range, the results of this macro are undefined.

Examples

start GeSHi

Print Bin(BitReset(&b10101, 2))
Print BitReset(5,0)
Print Hex(BitReset(&h8000000000000001,63))

end GeSHi

will produce the output:

10001
 4
1

Dialect Differences

• Not available in the -lang qb dialect unless referenced with the alias __Bitreset.

Differences from QB

• New to FreeBASIC.

See also

• Bit
• Bitset

Back to DocToc