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FFS(3)		       FreeBSD Library Functions Manual			FFS(3)

NAME
     ffs, ffsl,	ffsll, fls, flsl, flsll	-- find	first or last bit set in a bit
     string

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <strings.h>

     int
     ffs(int value);

     int
     ffsl(long value);

     int

     int
     ffsll(long	long value);

     fls(int value);

     int
     flsl(long value);

     int
     flsll(long	long value);

DESCRIPTION
     The ffs(),	ffsl() and ffsll() functions find the first bit	set (beginning
     with the least significant	bit) in	value and return the index of that
     bit.

     The fls(),	flsl() and flsll() functions find the last bit set in value
     and return	the index of that bit.

     Bits are numbered starting	at 1 (the least	significant bit).  A return
     value of zero from	any of these functions means that the argument was
     zero.

SEE ALSO
     bitstring(3)

HISTORY
     The ffs() function	appeared in 4.3BSD.  Its prototype existed previously
     in	<string.h> before it was moved to <strings.h> for IEEE Std 1003.1-2001
     (``POSIX.1'') compliance.

     The ffsl(), fls() and flsl() functions appeared in	FreeBSD	5.3.  The
     ffsll() and flsll() functions appeared in FreeBSD 8.0.

FreeBSD	11.1		       October 26, 2008			  FreeBSD 11.1
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | HISTORY

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