Name
getnetent, getnetbyname, getnetbyaddr, setnetent,
endnetent — get network entry
Synopsis
#include <netdb.h>
struct netent *getnetent( |
void); |
|
struct netent *getnetbyname( |
const char * |
name); |
struct netent *getnetbyaddr( |
long |
net, |
| |
int |
type); |
void
setnetent( |
int |
stayopen); |
DESCRIPTION
The getnetent() function
reads the next line from the file /etc/networks and returns a structure
netent containing
the broken out fields from the line. The /etc/networks file is opened if
necessary.
The getnetbyname() function
returns a netent
structure for the line from /etc/networks that matches the network
name.
The getnetbyaddr() function
returns a netent
structure for the line that matches the network number
net of type
type.
The setnetent() function
opens and rewinds the /etc/networks file. If stayopen is true (1), then the
file will not be closed between calls to getnetbyname() and getnetbyaddr().
The endnetent() function
closes /etc/networks.
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 */ |
| |
unsigned long |
|
n_net; |
/* network number */ |
| }; |
The members of the netent structure are:
n_name-
The official name of the network.
n_aliases-
A zero 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
The getnetent(),
getnetbyname() and getnetbyaddr() functions return the
netent structure,
or a NULL pointer if an error occurs or the end of the file
is reached.
FILES
/etc/networks-
networks database file
CONFORMING TO
4.3BSD, POSIX.1-2001.
SEE ALSO
getprotoent(3), getservent(3), networks(5)
RFC 1101
Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
Permission is granted to make and distribute verbatim copies of this
manual provided the copyright notice and this permission notice are
preserved on all copies.
Permission is granted to copy and distribute modified versions of this
manual under the conditions for verbatim copying, provided that the
entire resulting derived work is distributed under the terms of a
permission notice identical to this one.
Since the Linux kernel and libraries are constantly changing, this
manual page may be incorrect or out-of-date. The author(s) assume no
responsibility for errors or omissions, or for damages resulting from
the use of the information contained herein. The author(s) may not
have taken the same level of care in the production of this manual,
which is licensed free of charge, as they might when working
professionally.
Formatted or processed versions of this manual, if unaccompanied by
the source, must acknowledge the copyright and authors of this work.
References consulted:
Linux libc source code
Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
386BSD man pages
Modified Sat Jul 24 21:48:06 1993 by Rik Faith (faith@cs.unc.edu)
|
