rpcgen—An RPC protocol compiler
rpcgen [-D name[= value]] [-T] [-K secs] infile
rpcgen -c|-h|-l|-m|-t [-o outfile] infile
rpcgen [-I] -s nettype [-o outfile] infile
rpcgen -n netid [-o outfile] infile
rpcgen is a tool that generates C code to implement an RPC protocol. The input to rpcgen is a language similar to C known as RPC language (Remote Procedure Call Language). rpcgen is normally used as in the first synopsis where it takes an input file and generates up to four output files. If the infile is named proto.x, then rpcgen will generate a header file in proto.h, xdr routines in proto_xdr.c, server-side stubs in proto_svc.c, and client-side stubs in proto_clnt.c.
With the -T option, it will also generate the RPC dispatch table in proto_tbl.i. With the -Sc option, it will also generate sample code that would illustrate how to use the remote procedures on the client side. This code would be created in proto_client.c. With the -Ss option, it will also generate a sample server code that would illustrate how to write the remote procedures. This code would be created in proto_server.c. The server created can be started both by the port monitors (for example, inetd or listen) or by itself. When it is started by a port monitor, it creates servers only for the transport for which the file descriptor 0 was passed. The name of the transport must be specified by setting up the environmental variable PM_TRANSPORT.
When the server generated by rpcgen is executed, it creates server handles for all the transports specified in NETPATH environment variable, or if it is unset, it creates server handles for all the visible transports from /etc/netconfig file. Note: the transports are chosen at runtime and not at compile time. When the server is self-started, it backgrounds itself by default.
A special define symbol RPC_SVC_FG can be used to run the server process in the foreground. The second synopsis provides special features that allow for the creation of more sophisticated RPC servers. These features include support for userprovided #defines and RPC dispatch tables. The entries in the RPC dispatch table contain
- Pointers to the service routine corresponding to that procedure
- A pointer to the input and output arguments
- The size of these routines
A server can use the dispatch table to check authorization and then to execute the service routine; a client library may use it to deal with the details of storage management and xdr data conversion. The other three synopses shown in the preceding paragraph are used when one does not want to generate all the output files, but only a particular one. (Some examples of their usage is described in the “Example” subsection.) When rpcgen is executed with the -s option, it creates servers for that particular class of transports. When executed with the -n option, it creates a server for the transport specified by netid. If infile is not specified, rpcgen accepts the standard input. The C preprocessor, cc -E (see cc(1) for details), is run on the input file before it is actually interpreted by rpcgen. For each type of output file, rpcgen defines a special preprocessor symbol for use by the rpcgen programmer, as follows:
RPC_HDR Defined when compiling into header filesRPC_HDR Defined when compiling into header files
RPC_XDR Defined when compiling into XDR routines
RPC_SVC Defined when compiling into server-side stubs
RPC_CLNT Defined when compiling into client-side stubs
RPC_TBL Defined when compiling into RPC dispatch tables Any line beginning with % is passed directly into the output file, uninterpreted by rpcgen. For every data type referred to in infile, rpcgen assumes that there exists a routine with the string xdr prepended to the name of the data type. If this routine does not exist in the RPC/XDR library, it must be provided. Providing an undefined data type allows customization of XDR routines. The following options are available:
|-a||Generate all the files including sample code for client and server side.|
|-b||This generates code for the SunOS4.1 style of rpc. It is for backwards compatibility. This is the default.|
|-5||This generates code for the SysVr4 style of rpc. It is used by the Transport Independent RPC that is in Svr4 systems. By default, rpcgen generates code for SunOS4.1 type of rpc.|
|-c||Compile into XDR routines.|
|-C||Generate code in ANSI C. This option also generates code that could be compiled with the C++ compiler. This is the default.|
|-k||Generate code in K&R C. The default is ANSI C.|
|-Dname[=value]||Define a symbol name. Equivalent to the #define directive in the source. If no value is given, value is defined as 1. This option may be specified more than once.|
|-h||Compile into C data-definitions (a header file). -T option can be used in conjunction to produce a header file that supports RPC dispatch tables.|
|-I||Generate a service that can be started from inetd. The default is to generate a static service that handles transports selected with -s. Using -I allows starting a service by either method.|
|-K secs||By default, services created using rpcgen wait 120 seconds after servicing a request before exiting. That interval can be changed using the -K flag. To create a server that exits immediately upon servicing a request, -K 0 can be used. To create a server that never exits, the appropriate argument is -K -1.
When monitoring for a server, some port monitors, such as listen(1M), always spawn a new process in response to a service request. If it is known that a server will be used with such a monitor, the server should exit immediately on completion. For such servers, rpcgen should be used with -K -1.
|-l||Compile into client-side stubs.|
|-m||Compile into server-side stubs, but do not generate a main routine. This option is useful for doing callback-routines and for users who need to write their own main routine to do initialization.|
|-n netid||Compile into server-side stubs for the transport specified by netid. There should be an entry for netid in the netconfig database. This option may be specified more than once, so as to compile a server that serves multiple transports.|
|-N||Use the newstyle of rpcgen. This allows procedures to have multiple arguments. It also uses the style of parameter passing that closely resembles C. So, when passing an argument to a remote procedure, you do not have to pass a pointer to the argument but the argument itself. This behavior is different from the old style of rpcgengenerated code. The new style is not the default case because of backwards compatibility.|
|-o outfile||Specify the name of the output file. If none is specified, standard output is used (-c, -h, -l, -m, -n, -s, -sc, -ss, and -t modes only).|
|-s nettype||Compile into server-side stubs for all the transports belonging to the class nettype. The supported classes are netpath, visible, circuit_n, circuit_v, datagram_n, datagram_v, tcp, and udp. See rpc(3N) for the meanings associated with these classes. This option may be specified more than once. Note: The transports are chosen at runtime and not at compile time.|
|-Sc||Generate sample code to show the use of remote procedure and how to bind to the server before calling the client-side stubs generated by rpcgen.|
|-Ss||Generate skeleton code for the remote procedures on the server side. You would need to fill in the actual code for the remote procedures.|
|-t||Compile into RPC dispatch table.|
|-T||Generate the code to support RPC dispatch tables. The options -c, -h, -l, -m, u, and -t are used exclusively to generate a particular type of file, while the options -D and -T are global and can be used with the other options.|