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@(#)byteorder.3 8.1 (Berkeley) 6/4/93
$FreeBSD$

.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 n arpa/inet.h

p or

p n 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.

p 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 x 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.