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.Dd March 20, 2005
.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
.Pp
or
.Pp
.In netinet/in.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.
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 ,
.Xr byteorder 9
.Sh STANDARDS
The
.Nm byteorder
functions conform to
.St -p1003.1-2001 .
.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.