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GETNETENT(3)	       FreeBSD Library Functions Manual		  GETNETENT(3)

NAME
     getnetent,	getnetbyaddr, getnetbyname, setnetent, endnetent -- get	net-
     work entry

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #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
     The getnetent(), getnetbyname(), and getnetbyaddr() functions each	return
     a pointer to an object with the following structure describing an inter-
     net network.  This	structure contains either the information obtained
     from the nameserver, named(8), broken-out fields of a line	in the network
     data base /etc/networks, or entries supplied by the yp(8) system.	The
     order of the lookups is controlled	by the `networks' entry	in
     nsswitch.conf(5).

	   struct  netent {
		   char		   *n_name;	   /* official name of net */
		   char		   **n_aliases;	   /* alias list */
		   int		   n_addrtype;	   /* net number type */
		   uint32_t	   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.

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

     The setnetent() function opens and	rewinds	the file.  If the stayopen
     flag is non-zero, the net data base will not be closed after each call to
     getnetbyname() or getnetbyaddr().

     The endnetent() function closes the file.

     The getnetbyname()	function 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.  The type argument must be
     AF_INET.  Network numbers are supplied in host order.

FILES
     /etc/networks
     /etc/nsswitch.conf
     /etc/resolv.conf

DIAGNOSTICS
     Null pointer (0) returned on EOF or error.

SEE ALSO
     networks(5)

     RFC 1101

HISTORY
     The getnetent(), getnetbyaddr(), getnetbyname(), setnetent(), and
     endnetent() functions appeared in 4.2BSD.

BUGS
     The data space used by these functions is thread-specific;	if future use
     requires the data,	it should be copied before any subsequent calls	to
     these functions overwrite it.  Only Internet network numbers are cur-
     rently understood.	 Expecting network numbers to fit in no	more than 32
     bits is probably naive.

FreeBSD	10.1			 June 4, 1993			  FreeBSD 10.1

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | FILES | DIAGNOSTICS | SEE ALSO | HISTORY | BUGS

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