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)
          long net;

          setnetent(stayopen)
          int stayopen

          endnetent()

          cc ... -lnet

     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:

          nname      The official name of the network.

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

          naddrtype  The  type  of  the  network   number   returned;
                      currently only AFINET.

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

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

          setnetent opens and rewinds the file.  If the stayopen  flag



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     getnetent(3N)                                       getnetent(3N)



          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 is found, or  until  EOF  is  encountered.   Network
          numbers are supplied in host order.

     FILES
          /etc/networks

     LINKING
          This library is accessed by specifying  -lnet  as  the  last
          argument to the compile line, e.g.:

            cc -o prog prog.c -lnet

     SEE ALSO
          networks(4N)

     DIAGNOSTICS
          Null pointer (0) 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.  Expecting network numbers to  fit
          in no more than 32 bits is probably naive.
























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