Home Man
Today's Posts

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:
Select Section of Man Page:
Select Man Page Repository:

NetBSD 6.1.5 - man page for dns-sd (netbsd section 1)

dns-sd(1)			   BSD General Commands Manual				dns-sd(1)

     dns-sd -- Multicast DNS (mDNS) & DNS Service Discovery (DNS-SD) Test Tool

     dns-sd -R name type domain port [key=value ...]

     dns-sd -B type domain

     dns-sd -L name type domain

     The dns-sd command is a network diagnostic tool, much like ping(8) or traceroute(8).  How-
     ever, unlike those tools, most of its functionality is not implemented in the dns-sd exe-
     cutable itself, but in library code that is available to any application.	The library API
     that dns-sd uses is documented in /usr/include/dns_sd.h.

     The dns-sd command is primarily intended for interactive use.  Because its command-line
     arguments and output format are subject to change, invoking it from a shell script will gen-
     erally be fragile. Additionally, the asynchronous nature of DNS Service Discovery does not
     lend itself easily to script-oriented programming. For example, calls like "browse" never
     complete; the action of performing a "browse" sets in motion machinery to notify the client
     whenever instances of that service type appear or disappear from the network. These notifi-
     cations continue to be delivered indefinitely, for minutes, hours, or even days, as services
     come and go, until the client explicitly terminates the call. This style of asynchronous
     interaction works best with applications that are either multi-threaded, or use a main
     event-handling loop to receive keystrokes, network data, and other asynchronous event noti-
     fications as they happen.
     If you wish to perform DNS Service Discovery operations from a scripting language, then the
     best way to do this is not to execute the dns-sd command and then attempt to decipher the
     textual output, but instead to directly call the DNS-SD APIs using a binding for your chosen
     For example, if you are programming in Ruby, then you can directly call DNS-SD APIs using
     the dnssd package documented at <http://rubyforge.org/projects/dnssd/>.
     Similar bindings for other languages are also in development.

     dns-sd -R name type domain port [key=value ...]
	register (advertise) a service in the specified domain with the given name and type as
	listening (on the current machine) on port.

	name can be arbitrary unicode text, containing any legal unicode characters (including
	dots, spaces, slashes, colons, etc. without restriction), up to 63 UTF-8 bytes long.
	type must be of the form "_app-proto._tcp" or "_app-proto._udp", where "app-proto" is an
	application protocol name registered at http://www.dns-sd.org/ServiceTypes.html.

	domain is the domain in which to register the service.	In current implementations, only
	the local multicast domain "local" is supported. In the future, registering will be sup-
	ported in any arbitrary domain that has a working DNS Update server [RFC 2136]. The
	domain "." is a synonym for "pick a sensible default" which today means "local".

	port is a number from 0 to 65535, and is the TCP or UDP port number upon which the ser-
	vice is listening.

	Additional attributes of the service may optionally be described by key/value pairs,
	which are stored in the advertised service's DNS TXT record. Allowable keys and values
	are listed with the service registration at http://www.dns-sd.org/ServiceTypes.html.

     dns-sd -B type domain
	browse for instances of service type in domain.

	For valid types see http://www.dns-sd.org/ServiceTypes.html as described above. Omitting
	the domain or using "." means "pick a sensible default."

     dns-sd -L name type domain
	look up and display the information necessary to contact and use the named service: the
	hostname of the machine where that service is available, the port number on which the
	service is listening, and (if present) TXT record attributes describing properties of the

	Note that in a typical application, browsing happens rarely, while lookup (or "resolv-
	ing") happens every time the service is used. For example, a user browses the network to
	pick a default printer fairly rarely, but once a default printer has been picked, that
	named service is resolved to its current IP address and port number every time the user
	presses Cmd-P to print.

     To advertise the existence of LPR printing service on port 515 on this machine, such that it
     will be discovered by the Mac OS X printing software and other DNS-SD compatible printing
     clients, use:

	   dns-sd -R "My Test" _printer._tcp. . 515 pdl=application/postscript

     For this registration to be useful, you need to actually have LPR service available on port
     515. Advertising a service that does not exist is not very useful, and will be confusing and
     annoying to other people on the network.

     Similarly, to advertise a web page being served by an HTTP server on port 80 on this
     machine, such that it will show up in the Bonjour list in Safari and other DNS-SD compatible
     Web clients, use:

	   dns-sd -R "My Test" _http._tcp . 80 path=/path-to-page.html

     To find the advertised web pages on the local network (the same list that Safari shows),

	   dns-sd -B _http._tcp

     While that command is running, in another window, try the dns-sd -R example given above to
     advertise a web page, and you should see the "Add" event reported to the dns-sd -B window.
     Now press Ctrl-C in the dns-sd -R window and you should see the "Remove" event reported to
     the dns-sd -B window.



     The dns-sd command first appeared in NetBSD 6.0, having originated in Mac OS X 10.4 (Tiger).

NetBSD					 August 15, 2018				   NetBSD

All times are GMT -4. The time now is 03:04 AM.

Unix & Linux Forums Content Copyrightę1993-2018. All Rights Reserved.
Show Password

Not a Forum Member?
Forgot Password?