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netconfig(4)							  netconfig(4)

       netconfig - network configuration database


       The  network  configuration  database, /etc/netconfig, is a system file
       used to store information about networks	that are connected to the sys-
       tem.  The  netconfig database and the routines that access it (see get-
       netconfig(3NSL))	are part of the	Network	Selection component. The  Net-
       work  Selection	component  also	 includes getnetpath(3NSL) routines to
       provide application-specific network search paths. These	 routines  ac-
       cess  the netconfig database based on the environment variable NETPATH.
       See environ(5).

       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 ``\\''. Lines	in /etc/netconfig that begin with a # (hash) in	column
       1 are treated as	comments.

       Each  of	 the  valid  lines  in the netconfig database correspond to an
       available transport. Each entry is of the form:

	network	ID  semantics  flag  protocol-family
	protocol-name	network-device	translation-libraries

       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 signif-
			       icant 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
			       ``semantics''  of the network, that is, the set
			       of services it  supports,  by  identifying  the
			       service	interface  it  provides. The semantics
			       field is	mandatory. The following semantics are

			       tpi_clts	       Transport  Provider  Interface,

			       tpi_cots	       Transport  Provider  Interface,
					       connection oriented

			       tpi_cots_ord    Transport  Provider  Interface,
					       connection  oriented,  supports
					       orderly release.

       flag		       The   flag  field  records  certain  two-valued
			       (``true'' and  ``false'')  attributes  of  net-
			       works.  flag is a string	composed of a combina-
			       tion 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 at-
			       tribute is ``false.'' ``-'' indicates that none
			       of the attributes are present. Only one charac-
			       ter is currently	recognized:

			       v	       Visible (``default'')  network.
					       Used when the environment vari-
					       able NETPATH is unset.

       protocol	family	       The protocol family and	protocol  name	fields
			       are  provided  for  protocol-specific  applica-
			       tions. The protocol  family  field  contains  a
			       string  that  identifies	a protocol family. The
			       protocol	family	identifier  follows  the  same
			       rules as	those for network IDs; the string con-
			       sists of	non-null characters, 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 identi-
			       fier applies (the network is experimental). The
			       following are examples:

			       loopback	       Loopback	(local to host).

			       inet	       Internetwork: UDP, TCP, and the

			       inet6	       Internetwork  over  IPv6:  UDP,
					       TCP, and	the like.

			       implink	       ARPANET imp addresses

			       pup	       PUP protocols: for example, BSP

			       chaos	       MIT CHAOS protocols

			       ns	       XEROX NS	protocols

			       nbs	       NBS protocols

			       ecma	       European	Computer Manufacturers

			       datakit	       DATAKIT protocols

			       ccitt	       CCITT protocols,	X.25, and  the

			       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  (for  example,  protosw

			       x25	       CCITT X.25 in particular

			       osinet	       AFI = 47, IDI = 4

			       gosip	       U.S. Government OSI

       protocol	name	       The  protocol name field	contains a string that
			       identifies a protocol. The protocol name	 iden-
			       tifier follows the same rules as	those for net-
			       work 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.  A
			       ``-''  indicates	 that none of the names	listed
			       apply. The following protocol names are	recog-

			       tcp	       Transmission Control Protocol

			       udp	       User Datagram Protocol

			       icmp	       Internet	Control	Message	Proto-

       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  network  device  must be

       translation libraries   The name-to-address translation libraries  sup-
			       port a ``directory service'' (a name-to-address
			       mapping service)	for the	network.  A  ``-''  in
			       this  field indicates the absence of any	trans-
			       lation libraries. This has  a  special  meaning
			       for  networks of	the protocol family inet : its
			       name-to-address mapping is provided by the name
			       service	switch	based on the entries for hosts
			       and services in nsswitch.conf(4). For  networks
			       of  other families, a ``-'' indicates non-func-
			       tional name-to-address mapping. Otherwise, this
			       field  consists	of  a  comma-separated list of
			       pathnames to dynamically	linked libraries.  The
			       pathname	 of the	library	can be either absolute
			       or relative. See	dlopen(3C).

       Each field corresponds to an element in the struct netconfig structure.
       struct  netconfig and the identifiers described on this manual page are
       defined in <netconfig.h>. This structure	includes  the  following  mem-

       char *nc_netid			       Network ID, including NULL ter-

       unsigned	long nc_semantics	       Semantics.

       unsigned	long nc_flag		       Flags.

       char *nc_protofmly		       Protocol	family.

       char *nc_proto			       Protocol	name.

       char *nc_device			       Full pathname  of  the  network

       unsigned	long nc_nlookups	       Number  of directory lookup li-

       char **nc_lookups		       Names  of  the  name-to-address
					       translation libraries.

       unsigned	long nc_unused[9]	       Reserved	for future expansion.

       The nc_semantics	field takes the	following values, corresponding	to the
       semantics identified above:



		 NC_TPI_COTS_ORD The nc_flag field is a	bitfield. The  follow-
		 ing  bit, corresponding to the	attribute identified above, is
		 currently recognized. NC_NOFLAG indicates the absence of  any


       Example 1: A Sample netconfig File

       Below is	a sample netconfig file:

       #  The "Network Configuration" File.
       # Each entry is of the form:
       #   <networkid> <semantics> <flags> <protofamily> <protoname> <device>
       #	 <nametoaddrlibs>
       # The "-" in <nametoaddrlibs> for inet family transports	indicates
       # redirection to	the name service switch	policies for "hosts" and
       # "services". The "-" may be replaced by	nametoaddr libraries that
       # comply	with the SVr4 specs, in	which case the name service switch
       # will not be used for netdir_getbyname,	netdir_getbyaddr,
       # gethostbyname,	gethostbyaddr, getservbyname, and getservbyport.
       # There are no nametoaddr_libs for the inet family in Solaris anymore.
       udp6	  tpi_clts	v     inet6   udp    /dev/udp6	     -
       tcp6	  tpi_cots_ord	v     inet6   tcp    /dev/tcp6	     -
       udp	  tpi_clts	v     inet    udp    /dev/udp	     -
       tcp	  tpi_cots_ord	v     inet    tcp    /dev/tcp	     -
       rawip	  tpi_raw	-     inet    -	     /dev/rawip	     -
       ticlts	  tpi_clts	v    loopback -	     /dev/ticlts
       ticotsord  tpi_cots_ord	v    loopback -	     /dev/ticotsord
       ticots	  tpi_cots	v    loopback -	     /dev/ticots


       dlopen(3C), getnetconfig(3NSL), getnetpath(3NSL), nsswitch.conf(4)

				  18 Nov 2003			  netconfig(4)


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