'\"macro stdmacro
.\" Copyright (c) 1983 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)bstring.3	6.1 (Berkeley) 5/15/85
.\"
.TH BSTRING 3C  "May 15, 1985"
.UC 5
.SH NAME
bcopy, bcmp, blkclr, bzero, ffs \- bit and byte string operations
.SH SYNOPSIS
.B "#include <strings.h>"
.PP
.B "void bcopy(const void \(**src, void \(**dst, size_t length);
.PP
.B "int bcmp(const void \(**b1, const void \(**b2, size_t length);
.PP
.B "void bzero(void \(**b, size_t length);
.PP
.B "void blkclr(void \(**b, size_t length);
.PP
.B "int ffs(unsigned int i);"
.fi
.SH DESCRIPTION
The functions
.IR bcopy ,
.IR bcmp ,
and
.I bzero
operate on variable length strings of bytes.
They do not check for null bytes as the routines in
.IR string (3)
do.
.PP
.I bcopy
copies 
.I length
bytes from string
.I src
to the string
.IR dst .
.PP
.I bcmp
compares byte string
.I b1
against byte string
.IR b2 ,
returning zero if they are identical,
non-zero otherwise.  Both strings are
assumed to be
.I length
bytes long.
.PP
.I bzero
and
.I blkclr
place
.I length
zero bytes in the string
.IR b .
.PP
.I ffs
finds the first bit set in the argument passed it and
returns the index of that bit.  Bits are numbered
starting at 1.  A return value of 0 indicates the
value passed is zero.
.SH NOTE
The use of overlapping buffers with
.I bcopy
is not guaranteed to work.  Use
the 
.IR memmove (3C)
function if the buffers might overlap.
.SH SEE ALSO
memory(3c)
'\".so /pubs/tools/origin.bsd