net/byteorder.3

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  32 .\"     @(#)byteorder.3 8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/net/byteorder.3,v 1.8 2001/10/01 16:08:55 ru Exp $
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  35 .Dd June 4, 1993
  36 .Dt BYTEORDER 3
  37 .Os
  38 .Sh NAME
  39 .Nm htonl ,
  40 .Nm htons ,
  41 .Nm htonll ,
  42 .Nm ntohl ,
  43 .Nm ntohs ,
  44 .Nm ntohll
  45 .Nd convert values between host and network byte order
  46 .Sh LIBRARY
  47 .Lb libc
  48 .Sh SYNOPSIS
  49 .In arpa/inet.h
  50 .Ft uint64_t
  51 .Fn htonll "uint64_t hostlonglong"
  52 .Ft uint32_t
  53 .Fn htonl "uint32_t hostlong"
  54 .Ft uint16_t
  55 .Fn htons "uint16_t hostshort"
  56 .Ft uint64_t
  57 .Fn ntohll "uint64_t netlonglong"
  58 .Ft uint32_t
  59 .Fn ntohl "uint32_t netlong"
  60 .Ft uint16_t
  61 .Fn ntohs "uint16_t netshort"
  62 .Sh DESCRIPTION
  63 These routines convert 16 bit, 32 bit, and 64 bit quantities between network
  64 byte order and host byte order.
  65 (Network byte order is big endian, or most significant byte first.)
  66 On machines which have a byte order which is the same as the network
  67 order, routines are defined as null macros.
  68 .Pp
  69 These routines are most often used in conjunction with Internet
  70 addresses and ports as returned by
  71 .Xr gethostbyname 3
  72 and
  73 .Xr getservent 3 .
  74 .Sh SEE ALSO
  75 .Xr gethostbyname 3 ,
  76 .Xr getservent 3
  77 .Sh STANDARDS
  78 The
  79 .Nm byteorder
  80 functions except
  81 .Nm htonll
  82 and
  83 .Nm ntohll
  84 are expected to conform with IEEE Std POSIX.1-200x
  85 .Pq Dq POSIX.1
  86 .Sh HISTORY
  87 The
  88 functions
  89 .Nm htonl,
  90 .Nm htons,
  91 .Nm ntohl,
  92 .Nm ntohs
  93 appeared in
  94 .Bx 4.2 .
  95 .Pp
  96 The functions
  97 .Nm htonll
  98 and
  99 .Nm ntohll
 100 first appeared in OS X 10.10 (Yosemite).
 101 .Sh BUGS
 102 On the
 103 .Tn VAX
 104 bytes are handled backwards from most everyone else in
 105 the world.  This is not expected to be fixed in the near future.