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RPC_CLNT_CALLS(3)	 BSD Library Functions Manual	     RPC_CLNT_CALLS(3)

NAME
     rpc_clnt_calls, clnt_call,	clnt_freeres, clnt_geterr, clnt_perrno,
     clnt_perror, clnt_sperrno,	clnt_sperror, rpc_broadcast,
     rpc_broadcast_exp,	rpc_call -- library routines for client	side calls

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <rpc/rpc.h>

     enum clnt_stat
     clnt_call(CLIENT *clnt, const rpcproc_t procnum, const xdrproc_t inproc,
	 const caddr_t in, const xdrproc_t outproc, caddr_t out,
	 const struct timeval tout);

     bool_t
     clnt_freeres(CLIENT *clnt,	const xdrproc_t	outproc, caddr_t out);

     void
     clnt_geterr(const CLIENT *	clnt, struct rpc_err * errp);

     void
     clnt_perrno(const enum clnt_stat stat);

     void
     clnt_perror(CLIENT	*clnt, const char *s);

     char *
     clnt_sperrno(const	enum clnt_stat stat);

     char *
     clnt_sperror(CLIENT *clnt,	const char * s);

     enum clnt_stat
     rpc_broadcast(const rpcprog_t prognum, const rpcvers_t versnum,
	 const rpcproc_t procnum, const	xdrproc_t inproc, const	caddr_t	in,
	 const xdrproc_t outproc, caddr_t out, const resultproc_t eachresult,
	 const char *nettype);

     enum clnt_stat
     rpc_broadcast_exp(const rpcprog_t prognum,	const rpcvers_t	versnum,
	 const rpcproc_t procnum, const	xdrproc_t xargs, caddr_t argsp,
	 const xdrproc_t xresults, caddr_t resultsp,
	 const resultproc_t eachresult,	const int inittime,
	 const int waittime, const char	* nettype);

     enum clnt_stat
     rpc_call(const char *host,	const rpcprog_t	prognum,
	 const rpcvers_t versnum, const	rpcproc_t procnum,
	 const xdrproc_t inproc, const char *in, const xdrproc_t outproc,
	 char *out, const char *nettype);

DESCRIPTION
     RPC library routines allow	C language programs to make procedure calls on
     other machines across the network.	 First,	the client calls a procedure
     to	send a request to the server.  Upon receipt of the request, the	server
     calls a dispatch routine to perform the requested service,	and then sends
     back a reply.

     The clnt_call(), rpc_call(), and rpc_broadcast() routines handle the
     client side of the	procedure call.	 The remaining routines	deal with er-
     ror handling in the case of errors.

     Some of the routines take a CLIENT	handle as one of the arguments.	 A
     CLIENT handle can be created by an	RPC creation routine such as
     clnt_create() (see	rpc_clnt_create(3)).

     These routines are	safe for use in	multithreaded applications.  CLIENT
     handles can be shared between threads, however in this implementation re-
     quests by different threads are serialized	(that is, the first request
     will receive its results before the second	request	is sent).

Routines
     See rpc(3)	for the	definition of the CLIENT data structure.

     clnt_call()
	    A function macro that calls	the remote procedure procnum associ-
	    ated with the client handle, clnt, which is	obtained with an RPC
	    client creation routine such as clnt_create() (see
	    rpc_clnt_create(3)).  The inproc argument is the XDR function used
	    to encode the procedure's arguments, and outproc is	the XDR	func-
	    tion used to decode	the procedure's	results; in is the address of
	    the	procedure's argument(s), and out is the	address	of where to
	    place the result(s).  The tout argument is the time	allowed	for
	    results to be returned, which is overridden	by a time-out set ex-
	    plicitly through clnt_control(), see rpc_clnt_create(3).  If the
	    remote call	succeeds, the status returned is RPC_SUCCESS, other-
	    wise an appropriate	status is returned.

     clnt_freeres()
	    A function macro that frees	any data allocated by the RPC/XDR sys-
	    tem	when it	decoded	the results of an RPC call.  The out argument
	    is the address of the results, and outproc is the XDR routine de-
	    scribing the results.  This	routine	returns	1 if the results were
	    successfully freed,	and 0 otherwise.

     clnt_geterr()
	    A function macro that copies the error structure out of the	client
	    handle to the structure at address errp.

     clnt_perrno()
	    Print a message to standard	error corresponding to the condition
	    indicated by stat.	A newline is appended.	Normally used after a
	    procedure call fails for a routine for which a client handle is
	    not	needed,	for instance rpc_call().

     clnt_perror()
	    Print a message to the standard error indicating why an RPC	call
	    failed; clnt is the	handle used to do the call.  The message is
	    prepended with string s and	a colon.  A newline is appended.  Nor-
	    mally used after a remote procedure	call fails for a routine which
	    requires a client handle, for instance clnt_call().

     clnt_sperrno()
	    Take the same arguments as clnt_perrno(), but instead of sending a
	    message to the standard error indicating why an RPC	call failed,
	    return a pointer to	a string which contains	the message.  The
	    clnt_sperrno() function is normally	used instead of	clnt_perrno()
	    when the program does not have a standard error (as	a program run-
	    ning as a server quite likely does not), or	if the programmer does
	    not	want the message to be output with printf() (see printf(3)),
	    or if a message format different than that supported by
	    clnt_perrno() is to	be used.  Note:	unlike clnt_sperror() and
	    clnt_spcreateerror() (see rpc_clnt_create(3)), clnt_sperrno() does
	    not	return pointer to static data so the result will not get over-
	    written on each call.

     clnt_sperror()
	    Like clnt_perror(),	except that (like clnt_sperrno()) it returns a
	    string instead of printing to standard error.  However,
	    clnt_sperror() does	not append a newline at	the end	of the mes-
	    sage.  Warning: returns pointer to a buffer	that is	overwritten on
	    each call.

     rpc_broadcast()
	    Like rpc_call(), except the	call message is	broadcast to all the
	    connectionless transports specified	by nettype.  If	nettype	is
	    NULL, it defaults to "netpath".  Each time it receives a response,
	    this routine calls eachresult(), whose form	is: bool_t
	    eachresult(caddr_t out, const struct netbuf	* addr,	const struct
	    netconfig *	netconf) where out is the same as out passed to
	    rpc_broadcast(), except that the remote procedure's	output is de-
	    coded there; addr points to	the address of the machine that	sent
	    the	results, and netconf is	the netconfig structure	of the trans-
	    port on which the remote server responded.	If eachresult()	re-
	    turns 0, rpc_broadcast() waits for more replies; otherwise it re-
	    turns with appropriate status.  Warning: broadcast file descrip-
	    tors are limited in	size to	the maximum transfer size of that
	    transport.	For Ethernet, this value is 1500 bytes.	 The
	    rpc_broadcast() function uses AUTH_SYS credentials by default (see
	    rpc_clnt_auth(3)).

     rpc_broadcast_exp()
	    Like rpc_broadcast(), except that the initial timeout, inittime
	    and	the maximum timeout, waittime are specified in milliseconds.
	    The	inittime argument is the initial time that rpc_broadcast_exp()
	    waits before resending the request.	 After the first resend, the
	    re-transmission interval increases exponentially until it exceeds
	    waittime.

     rpc_call()
	    Call the remote procedure associated with prognum, versnum,	and
	    procnum on the machine, host.  The inproc argument is used to en-
	    code the procedure's arguments, and	outproc	is used	to decode the
	    procedure's	results; in is the address of the procedure's argu-
	    ment(s), and out is	the address of where to	place the result(s).
	    The	nettype	argument can be	any of the values listed on rpc(3).
	    This routine returns RPC_SUCCESS if	it succeeds, or	an appropriate
	    status is returned.	 Use the clnt_perrno() routine to translate
	    failure status into	error messages.	 Warning: rpc_call() uses the
	    first available transport belonging	to the class nettype, on which
	    it can create a connection.	 You do	not have control of timeouts
	    or authentication using this routine.

SEE ALSO
     printf(3),	rpc(3),	rpc_clnt_auth(3), rpc_clnt_create(3)

BSD				  May 7, 1993				   BSD

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | Routines | SEE ALSO

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