inet(3N)               (User Environment Utilities)                inet(3N)


   NAME
         inetaddr, inetnetwork, inetmakeaddr, inetlnaof, inetnetof,
         inetntoa - Internet address manipulation

   SYNOPSIS
         #include <sys/types.h>
         #include <sys/socket.h>
         #include <netinet/in.h>
         #include <arpa/inet.h>

         unsigned long
         inetaddr(cp)
         char *cp;

         inetnetwork(cp)
         char *cp;

         struct inaddr
         inetmakeaddr(net, lna)
         int net, lna;

         inetlnaof(in)
         struct inaddr in;

         inetnetof(in)
         struct inaddr in;

         char *
         inetntoa(in)
         struct inaddr in;

   DESCRIPTION
         The routines inetaddr() and inetnetwork() each interpret character
         strings representing numbers expressed in the Internet standard `.'
         notation, returning numbers suitable for use as Internet addresses
         and Internet network numbers, respectively.  The routine
         inetmakeaddr() takes an Internet network number and a local network
         address and constructs an Internet address from it.  The routines
         inetnetof() and inetlnaof() break apart Internet host addresses,
         returning the network number and local network address part,
         respectively.

         The routine inetntoa() returns a pointer to a string in the base 256
         notation d.d.d.d described below.

         All Internet addresses are returned in network order (bytes ordered
         from left to right).  All network numbers and local address parts are
         returned as machine format integer values.





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   inet(3N)               (User Environment Utilities)                inet(3N)


   INTERNET ADDRESSES
         Values specified using the `.'  notation take one of the following
         forms:


               a.b.c.d
               a.b.c
               a.b
               a

         When four parts are specified, each is interpreted as a byte of data
         and assigned, from left to right, to the four bytes of an Internet
         address.

         When a three part address is specified, the last part is interpreted
         as a 16-bit quantity and placed in the right most two bytes of the
         network address.  This makes the three part address format convenient
         for specifying Class B network addresses as 128.net.host.

         When a two part address is supplied, the last part is interpreted as
         a 24-bit quantity and placed in the right most three bytes of the
         network address.  This makes the two part address format convenient
         for specifying Class A network addresses as net.host.

         When only one part is given, the value is stored directly in the
         network address without any byte rearrangement.

         All numbers supplied as parts in a `.'  notation may be decimal,
         octal, or hexadecimal, as specified in the C language (that is, a
         leading 0x or 0X implies hexadecimal; otherwise, a leading 0 implies
         octal; otherwise, the number is interpreted as decimal).

   SEE ALSO
         gethostent(3N), getnetent(3N), hosts(4), networks(4)

   DIAGNOSTICS
         The value -1 is returned by inetaddr() and inetnetwork() for
         malformed requests.

   BUGS
         The problem of host byte ordering versus network byte ordering is
         confusing.  A simple way to specify Class C network addresses in a
         manner similar to that for Class B and Class A is needed.

         The return value from inetntoa() points to static information which
         is overwritten in each call.







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