1 '\" te
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  11 .TH FFS 3C "Jul 24, 2002"
  12 .SH NAME
  13 ffs \- find first set bit
  14 .SH SYNOPSIS
  15 .LP
  16 .nf
  17 #include <strings.h>
  18 
  19 \fBint\fR \fBffs\fR(\fBint\fR \fIi\fR);
  20 
  21 \fBint\fR \fBffsl\fR(\flong\fR \fIi\fR);
  22 
  23 \fBint\fR \fBffsll\fR(\fBlong long\fR \fIi\fR);
  24 
  25 \fBint\fR \fBfls\fR(\fBint\fR \fIi\fR);
  26 
  27 \fBint\fR \fBflsl\fR(\fBlong\fR \fIi\fR);
  28 
  29 \fBint\fR \fBflsl\fR(\fBlong long\fR \fIi\fR);
  30 .fi
  31 
  32 .SH DESCRIPTION
  33 .LP
  34 The \fBffs()\fR, \fBffsl()\, and \fBffsll()\fR functions finds the first bit set
  35 (beginning with the least significant bit) and return the index of that bit.
  36 Bits are numbered starting at one (the least significant bit).
  37 .sp
  38 .LP
  39 The \fBfls()\fR, \fBflsl()\fR, and \fBflsll()\fR functions find the last bit set
  40 (beginning with the most significant bit) and return the index of that bit.
  41 Bits are numbered starting at one (the least significant bit).
  42 .SH RETURN VALUES
  43 .LP
  44 The \fBffs()\fR, \fBffsl()\fR, and \fBffsll()\fR functions returns the index of
  45 the first bit set.  If \fIi\fR is 0, then they return 0.
  46 .sp
  47 .LP
  48 The \fBfls()\fR, \fBflsl()\fR, and \fBflsll()\fR functions return the index of
  49 the last bit set.  If \fIi\fR is 0, then they return 0.
  50 .SH ERRORS
  51 .LP
  52 No errors are defined.
  53 .SH ATTRIBUTES
  54 .LP
  55 See \fBattributes\fR(5) for descriptions of the following attributes:
  56 .sp
  57 
  58 .sp
  59 .TS
  60 box;
  61 c | c
  62 l | l .
  63 ATTRIBUTE TYPE  ATTRIBUTE VALUE
  64 _
  65 Interface Stability     Committed
  66 _
  67 MT-Level        MT-Safe
  68 .TE
  69 
  70 .SH SEE ALSO
  71 .LP
  72 \fBattributes\fR(5), \fBstandards\fR(5)