NETWORKS(5) File Formats and Configurations NETWORKS(5)
NAME
networks - network name database
SYNOPSIS
/etc/inet/networks /etc/networksDESCRIPTION
The
networks file is a local source of information regarding the
networks which comprise the Internet. The networks file can be used
in conjunction with, or instead of, other networks sources, including
the NIS maps
networks.byname and
networks.byaddr. Programs use the
getnetbyname(3SOCKET) routines to access this information.
The network file has a single line for each network, with the
following information:
official-network-name network-number aliases Items are separated by any number of
SPACE or
TAB characters. A `
#'
indicates the beginning of a comment. Characters up to the end of the
line are not interpreted by routines which search the file. This file
is normally created from the official network database maintained at
the Network Information Control Center (NIC), though local changes
may be required to bring it up to date regarding unofficial aliases
and/or unknown networks.
Network numbers may be specified in the conventional dot (`
.')
notation using the
inet_network routine from the Internet address
manipulation library,
inet(3C). Network names may contain any
printable character other than a field delimiter,
NEWLINE, or comment
character.
SEE ALSO
inet(3C),
getnetbyaddr(3SOCKET),
getnetbyname(3SOCKET),
nsswitch.conf(5)NOTES
The official SVR4 name of the
networks file is
/etc/inet/networks.
The symbolic link
/etc/networks exists for
BSD compatibility.
The network number in
networks database is the host address shifted
to the right by the number of 0 bits in the address mask. For
example, for the address
24.132.47.86 that has a mask of
fffffe00,
its network number is
803351. This is obtained when the address is
shifted right by 9 bits. The address maps to
12.66.23. The trailing 0
bits should not be specified. The network number here is different
from that described in
netmasks(5). For this example, the entry in
netmasks would be
24.132.46.0 fffffe00.
March 30, 2022 NETWORKS(5)
