blank.gif (43 bytes)

Church Of The
Swimming Elephant

3.2 Port Mapper Operation Connected: An Internet Encyclopedia
3.2 Port Mapper Operation

Up: Connected: An Internet Encyclopedia
Up: Requests For Comments
Up: RFC 1833
Up: 3. Port Mapper Program Protocol
Prev: 3.1 Port Mapper Protocol Specification (in RPC Language)
Next: References

3.2 Port Mapper Operation

3.2 Port Mapper Operation

The portmapper program currently supports two protocols (UDP and TCP). The portmapper is contacted by talking to it on assigned port number 111 (SUNRPC) on either of these protocols.

The following is a description of each of the portmapper procedures:


This procedure does no work. By convention, procedure zero of any protocol takes no parameters and returns no results.


When a program first becomes available on a machine, it registers itself with the port mapper program on the same machine. The program passes its program number "prog", version number "vers", transport protocol number "prot", and the port "port" on which it awaits service request. The procedure returns a boolean reply whose value is "TRUE" if the procedure successfully established the mapping and "FALSE" otherwise. The procedure refuses to establish a mapping if one already exists for the tuple "(prog, vers, prot)".


When a program becomes unavailable, it should unregister itself with the port mapper program on the same machine. The parameters and results have meanings identical to those of "PMAPPROC_SET". The protocol and port number fields of the argument are ignored.


Given a program number "prog", version number "vers", and transport protocol number "prot", this procedure returns the port number on which the program is awaiting call requests. A port value of zeros means the program has not been registered. The "port" field of the argument is ignored.


This procedure enumerates all entries in the port mapper's database. The procedure takes no parameters and returns a list of program, version, protocol, and port values.


This procedure allows a client to call another remote procedure on the same machine without knowing the remote procedure's port number. It is intended for supporting broadcasts to arbitrary remote programs via the well-known port mapper's port. The parameters "prog", "vers", "proc", and the bytes of "args" are the program number, version number, procedure number, and parameters of the remote procedure. Note:

  1. This procedure only sends a reply if the procedure was successfully executed and is silent (no reply) otherwise.

  2. The port mapper communicates with the remote program using UDP only.

The procedure returns the remote program's port number, and the reply is the reply of the remote procedure.

Next: References

Connected: An Internet Encyclopedia
3.2 Port Mapper Operation


Protect yourself from cyberstalkers, identity thieves, and those who would snoop on you.
Stop spam from invading your inbox without losing the mail you want. We give you more control over your e-mail than any other service.
Block popups, ads, and malicious scripts while you surf the net through our anonymous proxies.
Participate in Usenet, host your web files, easily send anonymous messages, and more, much more.
All private, all encrypted, all secure, all in an easy to use service, and all for only $5.95 a month!

Service Details

Have you gone to church today?
All pages ©1999, 2000, 2001, 2002, 2003 Church of the Swimming Elephant unless otherwise stated
Church of the Swimming Elephant©1999, 2000, 2001, 2002, 2003 is a wholly owned subsidiary of Packetderm, LLC.

Packetderm, LLC
210 Park Ave #308
Worcester, MA 01609