getnetent
NAME
getnetent, getnetbyname, getnetbyaddr, setnetent, endnetent -
get network entry
SYNOPSIS
#include <netdb.h> struct netent *getnetent(void); I struct netent *getnetbyname(const char * name ); I struct netent *getnetbyaddr(long net , int type ); I void setnetent(int stayopen ); void endnetent(void);
DESCRIPTION
The
R 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
R getnetbyname ()
function returns a netent structure
for the line from /etc/networks that matches the network
name.
The
R getnetbyaddr ()
function returns a netent structure
for the line that matches the network number net of type
type.
The
R setnetent ()
function opens and rewinds the
/etc/networks file.
If stayopen is true (1), then the
file will not be closed between calls to
R getnetbyname ()
and
R getnetbyaddr ().
The
R 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
R AF_INET .
n_net
The network number in host byte order.
RETURN VALUE
The
R getnetent (),
R getnetbyname ()
and
R 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.
ČLÁNKY DO MAILU