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.Dd June 4, 1993
.Dt BYTEORDER 3
.Os BSD 4.2
.Sh NAME
.Nm htonl ,
.Nm htons ,
.Nm ntohl ,
.Nm ntohs
.Nd convert values between host and network byte order
.Sh SYNOPSIS
.Fd #include <sys/types.h>
.Fd #include <machine/endian.h>
.Ft u_int32_t
.Fn htonl "u_int32_t host32"
.Ft u_int16_t
.Fn htons "u_int16_t host16"
.Ft u_int32_t
.Fn ntohl "u_int32_t net32"
.Ft u_int16_t
.Fn ntohs "u_int16_t net16"
.Sh DESCRIPTION
These routines convert 16 and 32 bit quantities between network
byte order and host byte order.  The last letter (s/l) is a mnemonic
for the traditional names for such quantities, short and long,
respectively.  Today, the C concept of "short"/"long" integers
need not coincide with this traditional misunderstanding.
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 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.