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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | FILES | CONFORMING TO | NOTES | SEE ALSO | COLOPHON


GETNETENT(3)                  Linux Programmer's Manual                  GETNETENT(3)

NAME         top

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

SYNOPSIS         top

       #include <netdb.h>

       struct netent *getnetent(void);

       struct netent *getnetbyname(const char *name);

       struct netent *getnetbyaddr(uint32_t net, int type);

       void setnetent(int stayopen);

       void endnetent(void);

DESCRIPTION         top

       The getnetent() function reads the next entry from the networks database and
       returns a netent structure containing the broken-out fields from the entry.  A
       connection is opened to the database if necessary.

       The getnetbyname() function returns a netent structure for the entry from the
       database that matches the network name.

       The getnetbyaddr() function returns a netent structure for the entry from the
       database that matches the network number net of type type.  The net argument
       must be in host byte order.

       The setnetent() function opens a connection to the database, and sets the next
       entry to the first entry.  If stayopen is non-zero, then the connection to the
       database will not be closed between calls to one of the getnet*() functions.

       The endnetent() function closes the connection to the database.

       The netent structure is defined in <netdb.h> as follows:

           struct netent {
               char      *n_name;     /* official network name */
               char     **n_aliases;  /* alias list */
               int        n_addrtype; /* net address type */
               uint32_t   n_net;      /* network number */
           }

       The members of the netent structure are:

       n_name The official name of the network.

       n_aliases
              A NULL-terminated list of alternative names for the network.

       n_addrtype
              The type of the network number; always AF_INET.

       n_net  The network number in host byte order.

RETURN VALUE         top

       The getnetent(), getnetbyname() and getnetbyaddr() functions return a pointer
       to a statically allocated netent structure, or a NULL pointer if an error
       occurs or the end of the file is reached.

FILES         top

       /etc/networks
              networks database file

CONFORMING TO         top

       4.3BSD, POSIX.1-2001.

NOTES         top

       In glibc versions before 2.2, the net argument of getnetbyaddr() was of type
       long.

SEE ALSO         top

       getnetent_r(3), getprotoent(3), getservent(3)
       RFC 1101

COLOPHON         top

       This page is part of release 3.23 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can be found
       at http://www.kernel.org/doc/man-pages/.

GNU                                   2008-08-19                         GETNETENT(3)