lib/libc/string/ffs.3 - master - nerfur/openbsd-src

lib/libc/string/ffs.3
61 строка2 KB
deraadt
adapt to bitstring(3) renaming, and look at that bit_ffs(3) is the actual
30 авг 2019, 21:35
30 авг 2019, 21:35656f8b8
.\" Copyright (c) 1990, 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" Chris Torek.
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.\"	$OpenBSD: ffs.3,v 1.11 2019/08/30 18:35:03 deraadt Exp $
.\"
.Dd $Mdocdate: August 30 2019 $
.Dt FFS 3
.Os
.Sh NAME
.Nm ffs
.Nd find first bit set in a bit string
.Sh SYNOPSIS
.In strings.h
.Ft int
.Fn ffs "int value"
.Sh DESCRIPTION
The
.Fn ffs
function finds the first bit set in
.Fa value
and returns the index of that bit.
Bits are numbered starting from 1, starting at the rightmost bit.
A return value of 0 means that the argument was zero.
.Sh SEE ALSO
.Xr bit_ffs 3
.Sh STANDARDS
The
.Fn ffs
function conforms to
.St -p1003.1-2008 .
.Sh HISTORY
The
.Fn ffs
function first appeared in
.Bx 4.2 .