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BYTEORDER(3)             BSD Library Functions Manual             BYTEORDER(3)

NAME
     htonl, htons, ntohl, ntohs -- convert values between host and network
     byte order

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <arpa/inet.h>

     uint32_t
     htonl(uint32_t hostlong);

     uint16_t
     htons(uint16_t hostshort);

     uint32_t
     ntohl(uint32_t netlong);

     uint16_t
     ntohs(uint16_t netshort);

DESCRIPTION
     These routines convert 16 and 32 bit quantities between network byte
     order and host byte order.  (Network byte order is big endian, or most
     significant byte first.)  On machines which have a byte order which is
     the same as the network order, routines are defined as null macros.

     These routines are most often used in conjunction with Internet addresses
     and ports as returned by gethostbyname(3) and getservent(3).

SEE ALSO
     gethostbyname(3), getservent(3)

STANDARDS
     The byteorder functions are expected to conform with IEEE Std
     POSIX.1-200x (``POSIX.1'').

HISTORY
     The byteorder functions appeared in 4.2BSD.

BUGS
     On the VAX bytes are handled backwards from most everyone else in the
     world.  This is not expected to be fixed in the near future.

BSD                              June 4, 1993                              BSD