The University of Auckland - Unix man pages: rpcgen (1)

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rpcgen(1) rpcgen(1)

NAME
rrppccggeenn - an RPC protocol compiler

SYNOPSIS
rrppccggeenn infile
rrppccggeenn [[--DDname[[==value]]]] [[--TT]] [[--KK secs]] infile
rrppccggeenn --cc||--hh||--ll||--mm||--tt [[--oo outfile ]] infile
rrppccggeenn [[--II]] --ss nettype [[--oo outfile]] infile
rrppccggeenn --nn netid [[--oo outfile]] infile

DESCRIPTION
rrppccggeenn is a tool that generates C code to implement an RPC
protocol. The input to rrppccggeenn is a language similar to C
known as RPC Language (Remote Procedure Call Language).

rrppccggeenn 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 pprroottoo..xx, then rrppccggeenn will generate
a header file in pprroottoo..hh, XDR routines in pprroottoo__xxddrr..cc,
server-side stubs in pprroottoo__ssvvcc..cc, and client-side stubs in
pprroottoo__ccllnntt..cc. With the --TT option, it will also generate
the RPC dispatch table in pprroottoo__ttbbll..ii. With the --SScc
option, it will also generate sample code which would
illustrate how to use the remote procedures on the client
side. This code would be created in pprroottoo__cclliieenntt..cc. With
the --SSss option, it will also generate a sample server code
which would illustrate how to write the remote procedures.
This code would be created in pprroottoo__sseerrvveerr..cc.

The server created can be started both by the port moni-
tors (for example, iinneettdd or lliisstteenn) or by itself. When it
is started by a port monitor, it creates servers only for
the transport for which the file descriptor 00 was passed.
The name of the transport must be specified by setting up
the environmental variable PPMM__TTRRAANNSSPPOORRTT. When the server
generated by rrppccggeenn is executed, it creates server handles
for all the transports specified in NNEETTPPAATTHH environment
variable, or if it is unset, it creates server handles for
all the visible transports from //eettcc//nneettccoonnffiigg file.
Note: the transports are chosen at run time and not at
compile time. When the server is self-started, it back-
grounds itself by default. A special define symbol
RRPPCC__SSVVCC__FFGG can be used to run the server process in fore-
ground.

The second synopsis provides special features which allow
for the creation of more sophisticated RPC servers. These
features include support for user provided ##ddeeffiinneess and
RPC dispatch tables. The entries in the RPC dispatch
table contain:
o pointers to the service routine corresponding to
that procedure,
o a pointer to the input and output arguments
o 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 above 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 section below. When rrppccggeenn is executed
with the --ss option, it creates servers for that particular
class of transports. When executed with the --nn option, it
creates a server for the transport specified by netid. If
infile is not specified, rrppccggeenn accepts the standard
input.

The C preprocessor, cccc --EE [see cccc(1)], is run on the input
file before it is actually interpreted by rrppccggeenn. For
each type of output file, rrppccggeenn defines a special prepro-
cessor symbol for use by the rrppccggeenn programmer:

RRPPCC__HHDDRR defined when compiling into header files
RRPPCC__XXDDRR defined when compiling into XDR routines
RRPPCC__SSVVCC defined when compiling into server-side stubs
RRPPCC__CCLLNNTT defined when compiling into client-side stubs
RRPPCC__TTBBLL defined when compiling into RPC dispatch
tables

Any line beginning with `%%' is passed directly into the
output file, uninterpreted by rrppccggeenn.

For every data type referred to in infile, rrppccggeenn assumes
that there exists a routine with the string xxddrr__ prepended
to the name of the data type. If this routine does not
exist in the RPC/XDR library, it must be provided. Pro-
viding an undefined data type allows customization of XDR
routines.

The following options are available:

--aa Generate all the files including sample code for
client and server side.

--bb This generates code for the SunOS4.1 style of rpc.
It is for backward compatibilty. This is the
default.

--55 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 stype of rpc.

--cc Compile into XDR routines.

--CC Generate code in ANSI C. This option also generates
code that could be compiled with the C++ compiler.
This is the default.

--kk Generate code in K&R C. The default is ANSI C.

--DDname[[==value]]
Define a symbol name. Equivalent to the ##ddeeffiinnee
directive in the source. If no value is given,
value is defined as 11. This option may be speci-
fied more than once.

--hh Compile into CC data-definitions (a header file).
--TT option can be used in conjunction to produce a
header file which supports RPC dispatch tables.

--II Generate a service that can be started from inetd.
The default is to generate a static service that
handles transports selected with --ss. Using --II
allows starting a service by either method.

--KK secs
By default, services created using rrppccggeenn wait 112200
seconds after servicing a request before exiting.
That interval can be changed using the --KK flag. To
create a server that exits immediately upon servic-
ing a request, --KK 00 can be used. To create a
server that never exits, the appropriate argument
is --KK --11.

When monitoring for a server, some portmonitors,
like lliisstteenn(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, rrppccggeenn should be used with --KK --11.

--ll Compile into client-side stubs.

--mm 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.

--nn 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.

--NN 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 behaviour is different
from the oldstyle of rpcgen generated code. The
newstyle is not the default case because of back-
ward compatibility.

--oo outfile
Specify the name of the output file. If none is
specified, standard output is used (--cc, --hh, --ll, --mm,
--nn, --ss, --ss --ssaanndd --tt modes only).

--ss nettype
Compile into server-side stubs for all the trans-
ports belonging to the class nettype. The sup-
ported classes are nneettppaatthh, vviissiibbllee, cciirrccuuiitt__nn,
cciirrccuuiitt__vv, ddaattaaggrraamm__nn, ddaattaaggrraamm__vv, ttccpp, and uuddpp
[see rrppcc(3N) for the meanings associated with these
classes]. This option may be specified more than
once. Note: the transports are chosen at run time
and not at compile time.

--SScc Generate sample code to show the use of remote pro-
cedure and how to bind to the server before calling
the client side stubs generated by rpcgen.

--SSss Generate skeleton code for the remote procedures on
the server side. You would need to fill in the
actual code for the remote procedures.

--tt Compile into RPC dispatch table.

--TT Generate the code to support RPC dispatch tables.

The options --cc, --hh, --ll, --mm, --ss and --tt are used exclusively
to generate a particular type of file, while the options
--DD and --TT are global and can be used with the other
options.

NOTES
The RPC Language does not support nesting of structures.
As a work-around, structures can be declared at the top-
level, and their name used inside other structures in
order to achieve the same effect.

Name clashes can occur when using program definitions,
since the apparent scoping does not really apply. Most of
these can be avoided by giving unique names for programs,
versions, procedures and types.

The server code generated with --nn option refers to the
transport indicated by netid and hence is very site spe-
cific.

EXAMPLE
The following example:

$$ rrppccggeenn --TT pprroott..xx

generates the five files: pprroott..hh, pprroott__ccllnntt..cc, pprroott__ssvvcc..cc,
pprroott__xxddrr..cc and pprroott__ttbbll..ii.

The following example sends the C data-definitions (header
file) to the standard output.

$$ rrppccggeenn --hh pprroott..xx

To send the test version of the --DDTTEESSTT, server side stubs
for all the transport belonging to the class ddaattaaggrraamm__nn to
standard output, use:

$$ rrppccggeenn --ss ddaattaaggrraamm__nn --DDTTEESSTT pprroott..xx

To create the server side stubs for the transport indi-
cated by netid ttccpp, use:

$$ rrppccggeenn --nn ttccpp --oo pprroott__ssvvcc..cc pprroott..xx

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