NETCONFIG(4-SVR4) RISC/os Reference Manual NETCONFIG(4-SVR4)
NAME
netconfig - network configuration database
SYNOPSIS
#include <netconfig.h>
DESCRIPTION
The network configuration database, /etc/netconfig, is a
system file used to store information about networks con-
nected to the system and available for use. The netconfig
database and the routines that access it [see
getnetconfig(3N)] are part of the UNIX System V Network
Selection component. The Network Selection component also
includes the environment variable NETPATH and a group of
routines that access the netconfig database using NETPATH
components as links to the netconfig entries. NETPATH is
described in sh(1); the NETPATH access routines are dis-
cussed in getnetpath(3N).
netconfig contains an entry for each network available on
the system. Entries are separated by newlines. Fields are
separated by whitespace and occur in the order in which they
are described below. Whitespace can be embedded as \blank
or \tab. Backslashes may be embedded as \\. Each field
corresponds to an element in the struct netconfig structure.
struct netconfig and the identifiers described on this
manual page are defined in /usr/include/netconfig.h.
network ID
A string used to uniquely identify a network. network
ID consists of non-null characters, and has a length
of at least 1. No maximum length is specified. This
namespace is locally significant and the local system
administrator is the naming authority. All network
IDs on a system must be unique.
semantics
The semantics field is a string identifying the seman-
tics of the network, i.e., the set of services it sup-
ports by identifying the service interface it pro-
vides. The semantics field is mandatory. The follow-
ing semantics are recognized:
tpi_clts Transport Provider Interface, connec-
tionless
tpi_cots Transport Provider Interface, connec-
tion oriented
tpi_cots_ord
Transport Provider Interface, connec-
tion oriented, supports orderly
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release.
flag The flag field records certain two-valued (true and
false) attributes of networks. flag is a string com-
posed of a combination of characters, each of which
indicates the value of the corresponding attribute.
If the character is present, the attribute is true.
If the character is absent, the attribute is false. -
indicates that none of the attributes is present.
Only one character is currently recognized:
v Visible (default) network. Used when
the environment variable NETPATH is
unset.
protocol family
The protocol family and protocol name fields are pro-
vided for protocol-specific applications.
The protocol family field contains a string that iden-
tifies a protocol family. The protocol family iden-
tifier follows the same rules as those for network
IDs, that is, the string consists of non-null charac-
ters; it has a length of at least 1; and there is no
maximum length specified. A - in the protocol family
field indicates that no protocol family identifier
applies, that is, the network is experimental. The
following are examples:
loopback Loopback (local to host).
inet Internetwork: UDP, TCP, etc.
implink ARPANET imp addresses
pup PUP protocols: e.g., BSP
chaos MIT CHAOS protocols
ns XEROX NS protocols
nbs NBS protocols
ecma European Computer Manufacturers Asso-
ciation
datakit DATAKIT protocols
ccitt CCITT protocols, X.25, etc.
sna IBM SNA
decnet DECNET
dli Direct data link interface
lat LAT
hylink NSC Hyperchannel
appletalk Apple Talk
nit Network Interface Tap
ieee802 IEEE 802.2; also ISO 8802
osi Umbrella for all families used by OSI
(e.g., protosw lookup)
x25 CCITT X.25 in particular
osinet AFI = 47, IDI = 4
gosip U.S. Government OSI
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NETCONFIG(4-SVR4) RISC/os Reference Manual NETCONFIG(4-SVR4)
protocol name
The protocol name field contains a string that identi-
fies a protocol. The protocol name identifier follows
the same rules as those for network IDs, that is, the
string consists of non-NULL characters; it has a
length of at least 1; and there is no maximum length
specified. The following protocol names are recog-
nized. A - indicates that none of the names listed
applies.
tcp Transmission Control Protocol
udp User Datagram Protocol
icmp Internet Control Message Protocol
network device
The network device is the full pathname of the device
used to connect to the transport provider. Typically,
this device will be in the /dev directory. The net-
work device must be specified.
directory lookup libraries
The directory lookup libraries support a directory
service (a name-to-address mapping service) for the
network. This service is implemented by the UNIX Sys-
tem V Name-to-Address Mapping feature. If a network
is not provided with such a library, the netdir
feature will not work. A - in this field indicates
the absence of any lookup libraries, in which case
name-to-address mapping for the network is non-
functional. The directory lookup library field con-
sists of a comma-separated list of full pathnames to
dynamically linked libraries. Commas may be embedded
as \, ; backslashes as \\.
Lines in /etc/netconfig that begin with a sharp sign (#) in
column 1 are treated as comments.
The struct netconfig structure includes the following
members corresponding to the fields in the netconfig data-
base entries:
char * nc_netid Network ID, including NULL
terminator
unsigned long nc_semantics Semantics
unsigned long nc_flag Flags
char * nc_protofmly Protocol family
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NETCONFIG(4-SVR4) RISC/os Reference Manual NETCONFIG(4-SVR4)
char * nc_proto Protocol name
char * nc_device Full pathname of the net-
work device
unsigned long nc_nlookups Number of directory lookup
libraries
char ** nc_lookups Full pathnames of the
directory lookup libraries
themselves
unsigned long nc_unused[9] Reserved for future expan-
sion (not advertised to
user level)
The nc_semantics field takes the following values,
corresponding to the semantics identified above:
NC_TPI_CLTS
NC_TPI_COTS
NC_TPI_COTS_ORD
The nc_flag field is a bitfield. The following bit,
corresponding to the attribute identified above, is
currently recognized. NC_NOFLAG indicates the absence of any
attributes.
NC_VISIBLE
SEE ALSO
netdir_getbyname(3N), getnetconfig(3N), getnetpath(3N),
netconfig(4)
Network Programmer's Guide
System Administrator's Guide
FILES
/etc/netconfig
/usr/include/netconfig.h
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