[apple/libc.git] / net / byteorder.3

.\" Copyright (c) 1983, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\"    must display the following acknowledgement:
.\"	This product includes software developed by the University of
.\"	California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\"    may be used to endorse or promote products derived from this software
.\"    without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\"     @(#)byteorder.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/net/byteorder.3,v 1.8 2001/10/01 16:08:55 ru Exp $
.\"
.Dd June 4, 1993
.Dt BYTEORDER 3
.Os
.Sh NAME
.Nm htonl ,
.Nm htons ,
.Nm ntohl ,
.Nm ntohs
.Nd convert values between host and network byte order
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In arpa/inet.h
.Ft uint32_t
.Fn htonl "uint32_t hostlong"
.Ft uint16_t
.Fn htons "uint16_t hostshort"
.Ft uint32_t
.Fn ntohl "uint32_t netlong"
.Ft uint16_t
.Fn ntohs "uint16_t netshort"
.Sh DESCRIPTION
These routines convert 16 and 32 bit quantities between network
byte order and host byte order.
(Network byte order is big endian, or most significant byte first.)
On machines which have a byte order which is the same as the network
order, routines are defined as null macros.
.Pp
These routines are most often used in conjunction with Internet
addresses and ports as returned by
.Xr gethostbyname 3
and
.Xr getservent 3 .
.Sh SEE ALSO
.Xr gethostbyname 3 ,
.Xr getservent 3
.Sh STANDARDS
The
.Nm byteorder
functions are expected to conform with IEEE Std POSIX.1-200x
.Pq Dq POSIX.1 .
.Sh HISTORY
The
.Nm byteorder
functions appeared in
.Bx 4.2 .
.Sh BUGS
On the
.Tn VAX
bytes are handled backwards from most everyone else in
the world.  This is not expected to be fixed in the near future.
Commit	Line	Data
5b2abdfb	1	.\" Copyright (c) 1983, 1991, 1993
e9ce8d39 A	2	.\" The Regents of the University of California. All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice, this list of conditions and the following disclaimer.
	9	.\" 2. Redistributions in binary form must reproduce the above copyright
	10	.\" notice, this list of conditions and the following disclaimer in the
	11	.\" documentation and/or other materials provided with the distribution.
	12	.\" 3. All advertising materials mentioning features or use of this software
	13	.\" must display the following acknowledgement:
	14	.\" This product includes software developed by the University of
	15	.\" California, Berkeley and its contributors.
	16	.\" 4. Neither the name of the University nor the names of its contributors
	17	.\" may be used to endorse or promote products derived from this software
	18	.\" without specific prior written permission.
	19	.\"
	20	.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	21	.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	22	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	23	.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	24	.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	25	.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	26	.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	27	.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	28	.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	29	.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	30	.\" SUCH DAMAGE.
	31	.\"
5b2abdfb A	32	.\" @(#)byteorder.3 8.1 (Berkeley) 6/4/93
5b2abdfb A	33	.\" $FreeBSD: src/lib/libc/net/byteorder.3,v 1.8 2001/10/01 16:08:55 ru Exp $
e9ce8d39	34	.\"
5b2abdfb A	35	.Dd June 4, 1993
5b2abdfb A	36	.Dt BYTEORDER 3
e9ce8d39 A	37	.Os
e9ce8d39 A	38	.Sh NAME
5b2abdfb A	39	.Nm htonl ,
	40	.Nm htons ,
	41	.Nm ntohl ,
	42	.Nm ntohs
	43	.Nd convert values between host and network byte order
e9ce8d39 A	44	.Sh LIBRARY
	45	.Lb libc
	46	.Sh SYNOPSIS
5b2abdfb A	47	.In arpa/inet.h
	48	.Ft uint32_t
	49	.Fn htonl "uint32_t hostlong"
	50	.Ft uint16_t
	51	.Fn htons "uint16_t hostshort"
	52	.Ft uint32_t
	53	.Fn ntohl "uint32_t netlong"
	54	.Ft uint16_t
	55	.Fn ntohs "uint16_t netshort"
e9ce8d39	56	.Sh DESCRIPTION
5b2abdfb A	57	These routines convert 16 and 32 bit quantities between network
5b2abdfb A	58	byte order and host byte order.
224c7076	59	(Network byte order is big endian, or most significant byte first.)
5b2abdfb A	60	On machines which have a byte order which is the same as the network
	61	order, routines are defined as null macros.
	62	.Pp
	63	These routines are most often used in conjunction with Internet
	64	addresses and ports as returned by
	65	.Xr gethostbyname 3
e9ce8d39	66	and
5b2abdfb	67	.Xr getservent 3 .
e9ce8d39	68	.Sh SEE ALSO
5b2abdfb A	69	.Xr gethostbyname 3 ,
	70	.Xr getservent 3
	71	.Sh STANDARDS
	72	The
	73	.Nm byteorder
	74	functions are expected to conform with IEEE Std POSIX.1-200x
	75	.Pq Dq POSIX.1 .
e9ce8d39 A	76	.Sh HISTORY
e9ce8d39 A	77	The
5b2abdfb A	78	.Nm byteorder
	79	functions appeared in
	80	.Bx 4.2 .
	81	.Sh BUGS
	82	On the
	83	.Tn VAX
	84	bytes are handled backwards from most everyone else in
	85	the world. This is not expected to be fixed in the near future.