[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] | Reference for unit 'System' (#rtl)

# BsfDWord

Return the position of the rightmost set bit in a 32-bit value

## Declaration

Source position: systemh.inc line 1105

`function BsfDWord(`
`const AValue: DWord`
`):Cardinal;`

## Description

BsfDWord scans the DWord AValue, starting at position 0 (rightmost position) , and returns the index of the first set bit. The position is measured from the 0-th, rightmost bit.

When the input is 0, the result is 255 (unsigned equivalent of -1).

## See also

BsfByte |  | Return the position of the rightmost set bit in an 8-bit value
BsfWord |  | Return the position of the rightmost set bit in a 16-bit value
BsrDWord |  | Return the position of the leftmost set bit in a 32-bit value
BsfQWord |  | Return the position of the rightmost set bit in a 64-bit value