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.TH FFS 3C "May 21, 2015"
.SH NAME
ffs \- find first set bit
.SH SYNOPSIS
.LP
.nf
#include <strings.h>

\fBint\fR \fBffs\fR(\fBint\fR \fIi\fR);

\fBint\fR \fBffsl\fR(\fBlong\fR \fIi\fR);

\fBint\fR \fBffsll\fR(\fBlong long\fR \fIi\fR);

\fBint\fR \fBfls\fR(\fBint\fR \fIi\fR);

\fBint\fR \fBflsl\fR(\fBlong\fR \fIi\fR);

\fBint\fR \fBflsll\fR(\fBlong long\fR \fIi\fR);
.fi

.SH DESCRIPTION
.LP
The \fBffs()\fR, \fBffsl()\fR, and \fBffsll()\fR functions finds the first bit set
(beginning with the least significant bit) and return the index of that bit.
Bits are numbered starting at one (the least significant bit).
.sp
.LP
The \fBfls()\fR, \fBflsl()\fR, and \fBflsll()\fR functions find the last bit set
(beginning with the least significant bit) and return the index of that bit.
Bits are numbered starting at one (the least significant bit).
.SH RETURN VALUES
.LP
The \fBffs()\fR, \fBffsl()\fR, and \fBffsll()\fR functions returns the index of
the first bit set.  If \fIi\fR is 0, then they return 0.
.sp
.LP
The \fBfls()\fR, \fBflsl()\fR, and \fBflsll()\fR functions return the index of
the last bit set.  If \fIi\fR is 0, then they return 0.
.SH ERRORS
.LP
No errors are defined.
.SH ATTRIBUTES
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
box;
c | c
l | l .
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Committed
_
MT-Level	MT-Safe
.TE

.SH SEE ALSO
.LP
.BR attributes (7),
.BR standards (7)