BYTEORDER(3N)       RISC/os Reference Manual        BYTEORDER(3N)



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

SYNOPSIS
   Headers
     For -systype sysv:

     #include <sys/types.h>
     #include <bsd/netinet/in.h>

     For -systype bsd43:

     #include <sys/types.h>
     #include <netinet/in.h>

   Declarations
     netlong = htonl(hostlong);
     ulong netlong, hostlong;

     netshort = htons(hostshort);
     ushort netshort, hostshort;

     hostlong = ntohl(netlong);
     ulong hostlong, netlong;

     hostshort = ntohs(netshort);
     ushort hostshort, netshort;

DESCRIPTION
     These routines convert 16 and 32 bit quantities between net-
     work byte order and host byte order.  These routines are
     defined as null macros in the include file
     <bsd/netinet/in.h> for -systype sysv and in <netinet/in.h>
     for -systype bsd43.

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

SEE ALSO
     gethostbyname(3N), getservent(3N).

NOTE
     When these routines are used in a program which is compiled
     in -systype sysv, they are not resolved by libc.a.  See
     intro(3-SysV) for more information.








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