getnetent(SLIB)                6 January 1993                getnetent(SLIB)


 Name

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

 Syntax


    #include  <netdb.h>

    struct netent *getnetent ( )

    struct netent *getnetbyname (name)
    char *name;

    struct netent *getnetbyaddr (net)
    long net;

    setnetent (stayopen)
    int stayopen;

    endnetent ( )


 Description

    getnetent, getnetbyname, and getnetbyaddr each returns 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 null-terminated list of alternate names for the network.

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

    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 is non-zero,
    the network 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 machine byte order.

 Files

    /etc/networks

 Diagnostics

    Null pointer (0) returned on EOF or error.

 Notes

    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.

 See also

    networks(SFF)