xref: /freebsd/lib/libc/net/byteorder.3 (revision 41466b50c1d5bfd1cf6adaae547a579a75d7c04e)
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32.\"     @(#)byteorder.3	8.1 (Berkeley) 6/4/93
33.\" $FreeBSD$
34.\"
35.Dd June 4, 1993
36.Dt BYTEORDER 3
37.Os
38.Sh NAME
39.Nm htonl ,
40.Nm htons ,
41.Nm ntohl ,
42.Nm ntohs
43.Nd convert values between host and network byte order
44.Sh LIBRARY
45.Lb libc
46.Sh SYNOPSIS
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"
56.Sh DESCRIPTION
57These routines convert 16 and 32 bit quantities between network
58byte order and host byte order.
59On machines which have a byte order which is the same as the network
60order, routines are defined as null macros.
61.Pp
62These routines are most often used in conjunction with Internet
63addresses and ports as returned by
64.Xr gethostbyname 3
65and
66.Xr getservent 3 .
67.Sh SEE ALSO
68.Xr gethostbyname 3 ,
69.Xr getservent 3
70.Sh STANDARDS
71The
72.Nm byteorder
73functions are expected to conform with IEEE Std POSIX.1-200x
74.Pq Dq POSIX.1 .
75.Sh HISTORY
76The
77.Nm byteorder
78functions appeared in
79.Bx 4.2 .
80.Sh BUGS
81On the
82.Tn VAX
83bytes are handled backwards from most everyone else in
84the world.  This is not expected to be fixed in the near future.
85