'\" te
.\" Copyright 1989 AT&T
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.TH ffs 3C "16 Jun 2015" "SunOS 5.11" "Standard C Library Functions"
.SH NAME
ffs, ffsl, ffsll, fls, flsl, flsll \- find first or last bit set in a bit string
.SH SYNOPSIS
.LP
.nf
#include <strings.h>

\fBint\fR \fBffs\fR(\fBint\fR \fIvalue\fR);
.fi

.LP
.nf
int ffsl(long \fIvalue\fR);
.fi

.LP
.nf
int ffsll(long long \fIvalue\fR);
.fi

.LP
.nf
int fls(int \fIvalue\fR);
.fi

.LP
.nf
int flsl(long \fIvalue\fR);
.fi

.LP
.nf
int flsll(long long \fIvalue\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBffs()\fR, \fBffsl()\fR, and \fBffsll()\fR functions find the first bit set in \fIvalue\fR and return the position of that bit.
.sp
.LP
The \fBfls()\fR, \fBfssl()\fR, and \fBflsll()\fR functions find the last bit set in \fIvalue\fR and return the position of that bit.
.sp
.LP
Bits are numbered starting at one (the least significant bit).
.SH RETURN VALUES
.sp
.LP
These  functions  return  the position of the first bit set, or 0 if no bits are set in \fIvalue\fR.
.SH ERRORS
.sp
.LP
No errors are defined.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
_
MT-LevelMT-Safe
_
StandardSee \fBstandards\fR(5).
.TE

.SH SEE ALSO
.sp
.LP
\fBattributes\fR(5), \fBstandards\fR(5)