portmap Operation

portmap currently supports two protocols (UDP/IP and TCP/IP). portmap is contacted by talking to it on assigned port number 111 (SUNRPC (5)) on either of these protocols. The following is a description of each of the portmapper procedures.

PMAPPROC_NULL

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

PMAPPROC_SET

When a program first becomes available on a machine, it registers itself with the local port map program. The program passes its program number prog, version number vers, transport protocol number prot, and the port port on which it receives service requests. The procedure refuses to establish a mapping if one already exists for the specified port and it is bound. If the mapping exists and the port is not bound, portmap unregisters the port and performs the requested mapping. The procedure returns TRUE if the procedure successfully established the mapping and FALSE otherwise. See also the pmap_set() function in the rpc_soc(3NSL) man page.

PMAPPROC_UNSET

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. See also the pmap_unset() function in the rpc_soc(3NSL) man page.

PMAPPROC_GETPORT

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. See also the pmap_getport() function in the rpc_soc(3NSL) man page.

PMAPPROC_DUMP

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. See also the pmap_getmaps() function in the rpc_soc(3NSL) man page.

PMAPPROC_CALLIT

This procedure allows a caller 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. See also the pmap_rmtcall() function in the rpc_soc(3NSL) man page.

This procedure only sends a response if the procedure was successfully executed and is silent (no response) otherwise. It also returns the remote program's port number, and the bytes of results are the results of the remote procedure.

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