xref: /freebsd/lib/libc/net/byteorder.3 (revision afe61c15161c324a7af299a9b8457aba5afc92db)
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32.\"     @(#)byteorder.3	8.1 (Berkeley) 6/4/93
33.\"
34.Dd June 4, 1993
35.Dt BYTEORDER 3
36.Os BSD 4.2
37.Sh NAME
38.Nm htonl ,
39.Nm htons ,
40.Nm ntohl ,
41.Nm ntohs
42.Nd convert values between host and network byte order
43.Sh SYNOPSIS
44.Fd #include <sys/param.h>
45.Ft u_long
46.Fn htonl "u_long hostlong"
47.Ft u_short
48.Fn htons "u_short hostshort"
49.Ft u_long
50.Fn ntohl "u_long netlong"
51.Ft u_short
52.Fn ntohs "u_short netshort"
53.Sh DESCRIPTION
54These routines convert 16 and 32 bit quantities between network
55byte order and host byte order.
56On machines which have a byte order which is the same as the network
57order, routines are defined as null macros.
58.Pp
59These routines are most often used in conjunction with Internet
60addresses and ports as returned by
61.Xr gethostbyname 3
62and
63.Xr getservent 3 .
64.Sh SEE ALSO
65.Xr gethostbyname 3 ,
66.Xr getservent 3
67.Sh HISTORY
68The
69.Nm byteorder
70functions appeared in
71.Bx 4.2 .
72.Sh BUGS
73On the
74.Tn VAX
75bytes are handled backwards from most everyone else in
76the world.  This is not expected to be fixed in the near future.
77