getnetent(3N)                                                 getnetent(3N)


   NAME
         getnetent, getnetbyaddr, getnetbyname, setnetent, endnetent - get
         network entry

   SYNOPSIS
         #include <netdb.h>

         struct netent *getnetent()

         struct netent *getnetbyname(name)
         char *name;

         struct netent *getnetbyaddr(net, type)
         long net;
         int type;

         setnetent(stayopen)
         int stayopen;

         endnetent()

   DESCRIPTION
         getnetent(), getnetbyname(), and getnetbyaddr() each return a pointer
         to an object with the following structure containing the broken-out
         fields of a line in the network data base, /etc/networks.

               struct      netent {
                     char  *n_name;    /* official name of net */
                     char  **n_aliases;      /* alias list */
                     int   n_addrtype; /* net number type */
                     long  n_net;            /* net number */
               };

         The members of this structure are:

               n_name              The official name of the network.

               n_aliases           A zero terminated list of alternate names
                                   for the network.

               n_addrtype          The type of the network number returned;
                                   currently only AF_INET.

               n_net               The network number.  Network numbers are
                                   returned in machine byte order.

         getnetent() reads the next line of the file, opening the file if
         necessary.





   7/91                                                                 Page 1

   getnetent(3N)                                                 getnetent(3N)


         setnetent() opens and rewinds the file.  If the stayopen flag is
         non-zero, the net data base will not be closed after each call to
         getnetent() (either directly, or indirectly through one of the other
         getnet calls).

         endnetent() closes the file.

         getnetbyname() and getnetbyaddr() sequentially search from the
         beginning of the file until a matching net name or net address and
         type is found, or until EOF is encountered.  Network numbers are
         supplied in host order.

   FILES
         /etc/networks

   SEE ALSO
         networks(4)

   DIAGNOSTICS
         A NULL pointer is returned on EOF or error.

   BUGS
         All information is contained in a static area so it must be copied if
         it is to be saved.

         Only Internet network numbers are currently understood.



























   Page 2                                                                 7/91