1.\" Copyright (c) 1990, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Chris Torek. 6.\" %sccs.include.redist.man% 7.\" 8.\" @(#)ffs.3 5.3 (Berkeley) 04/19/91 9.\" 10.Dd 11.Dt FFS 3 12.Os 13.Sh NAME 14.Nm ffs 15.Nd find first bit set in a bit string 16.Sh SYNOPSIS 17.Fd #include <string.h> 18.Ft int 19.Fn ffs "int value" 20.Sh DESCRIPTION 21The 22.Fn ffs 23fucntion 24finds the first bit set in 25.Fa value 26and returns the index of that bit. 27Bits are numbered starting from 1, starting at the right-most 28bit. 29A return value of 0 means that the argument was zero. 30.Sh SEE ALSO 31.Xr bitstring 3 32.Sh HISTORY 33The 34.Fn ffs 35function appeared in 36.Bx 4.3 . 37