1RPC_CLNT_CALLS(3) BSD Library Functions Manual RPC_CLNT_CALLS(3)
2
4 rpc_clnt_calls, clnt_call, clnt_freeres, clnt_geterr, clnt_perrno,
5 clnt_perror, clnt_sperrno, clnt_sperror, rpc_broadcast,
6 rpc_broadcast_exp, rpc_call — library routines for client side calls
7
9 #include <rpc/rpc.h>
10 enum clnt_stat
12 clnt_call(CLIENT *clnt, const rpcproc_t procnum, const xdrproc_t inproc,
13 const caddr_t in, const xdrproc_t outproc, caddr_t out,
14 const struct timeval tout);
15 bool_t
17 clnt_freeres(CLIENT *clnt, const xdrproc_t outproc, caddr_t out);
18 void
20 clnt_geterr(const CLIENT * clnt, struct rpc_err * errp);
21 void
23 clnt_perrno(const enum clnt_stat stat);
24 void
26 clnt_perror(CLIENT *clnt, const char *s);
27 char *
29 clnt_sperrno(const enum clnt_stat stat);
30 char *
32 clnt_sperror(CLIENT *clnt, const char * s);
33 enum clnt_stat
35 rpc_broadcast(const rpcprog_t prognum, const rpcvers_t versnum,
36 const rpcproc_t procnum, const xdrproc_t inproc, const caddr_t in,
37 const xdrproc_t outproc, caddr_t out, const resultproc_t eachresult,
38 const char *nettype);
39 enum clnt_stat
41 rpc_broadcast_exp(const rpcprog_t prognum, const rpcvers_t versnum,
42 const rpcproc_t procnum, const xdrproc_t xargs, caddr_t argsp,
43 const xdrproc_t xresults, caddr_t resultsp,
44 const resultproc_t eachresult, const int inittime,
45 const int waittime, const char * nettype);
46 enum clnt_stat
48 rpc_call(const char *host, const rpcprog_t prognum,
49 const rpcvers_t versnum, const rpcproc_t procnum,
50 const xdrproc_t inproc, const char *in, const xdrproc_t outproc,
51 char *out, const char *nettype);
52
54 RPC library routines allow C language programs to make procedure calls on
55 other machines across the network. First, the client calls a procedure
56 to send a request to the server. Upon receipt of the request, the server
57 calls a dispatch routine to perform the requested service, and then sends
58 back a reply.
59 The clnt_call(), rpc_call(), and rpc_broadcast() routines handle the
61 client side of the procedure call. The remaining routines deal with
62 error handling in the case of errors.
63 Some of the routines take a CLIENT handle as one of the arguments. A
65 CLIENT handle can be created by an RPC creation routine such as
66 clnt_create() (see rpc_clnt_create(3)).
67 These routines are safe for use in multithreaded applications. CLIENT
69 handles can be shared between threads, however in this implementation
70 requests by different threads are serialized (that is, the first request
71 will receive its results before the second request is sent).
72
74 See rpc(3) for the definition of the CLIENT data structure.
75 clnt_call()
77 A function macro that calls the remote procedure procnum associ‐
78 ated with the client handle, clnt, which is obtained with an RPC
79 client creation routine such as clnt_create() (see
80 rpc_clnt_create(3)). The inproc argument is the XDR function used
81 to encode the procedure's arguments, and outproc is the XDR func‐
82 tion used to decode the procedure's results; in is the address of
83 the procedure's argument(s), and out is the address of where to
84 place the result(s). The tout argument is the time allowed for
85 results to be returned, which is overridden by a time-out set
86 explicitly through clnt_control(), see rpc_clnt_create(3). If the
87 remote call succeeds, the status returned is RPC_SUCCESS, other‐
88 wise an appropriate status is returned.
89 clnt_freeres()
91 A function macro that frees any data allocated by the RPC/XDR sys‐
92 tem when it decoded the results of an RPC call. The out argument
93 is the address of the results, and outproc is the XDR routine
94 describing the results. This routine returns 1 if the results
95 were successfully freed, and 0 otherwise.
96 clnt_geterr()
98 A function macro that copies the error structure out of the client
99 handle to the structure at address errp.
100 clnt_perrno()
102 Print a message to standard error corresponding to the condition
103 indicated by stat. A newline is appended. Normally used after a
104 procedure call fails for a routine for which a client handle is
105 not needed, for instance rpc_call().
106 clnt_perror()
108 Print a message to the standard error indicating why an RPC call
109 failed; clnt is the handle used to do the call. The message is
110 prepended with string s and a colon. A newline is appended. Nor‐
111 mally used after a remote procedure call fails for a routine which
112 requires a client handle, for instance clnt_call().
113 clnt_sperrno()
115 Take the same arguments as clnt_perrno(), but instead of sending a
116 message to the standard error indicating why an RPC call failed,
117 return a pointer to a string which contains the message. The
118 clnt_sperrno() function is normally used instead of clnt_perrno()
119 when the program does not have a standard error (as a program run‐
120 ning as a server quite likely does not), or if the programmer does
121 not want the message to be output with printf() (see printf(3)),
122 or if a message format different than that supported by
123 clnt_perrno() is to be used. Note: unlike clnt_sperror() and
124 clnt_spcreateerror() (see rpc_clnt_create(3)), clnt_sperrno() does
125 not return pointer to static data so the result will not get over‐
126 written on each call.
127 clnt_sperror()
129 Like clnt_perror(), except that (like clnt_sperrno()) it returns a
130 string instead of printing to standard error. However,
131 clnt_sperror() does not append a newline at the end of the mes‐
132 sage. Warning: returns pointer to a buffer that is overwritten on
133 each call.
134 rpc_broadcast()
136 Like rpc_call(), except the call message is broadcast to all the
137 connectionless transports specified by nettype. If nettype is
138 NULL, it defaults to "netpath". Each time it receives a response,
139 this routine calls eachresult(), whose form is: bool_t
140 eachresult(caddr_t out, const struct netbuf * addr, const struct
141 netconfig * netconf) where out is the same as out passed to
142 rpc_broadcast(), except that the remote procedure's output is
143 decoded there; addr points to the address of the machine that sent
144 the results, and netconf is the netconfig structure of the trans‐
145 port on which the remote server responded. If eachresult()
146 returns 0, rpc_broadcast() waits for more replies; otherwise it
147 returns with appropriate status. Warning: broadcast file descrip‐
148 tors are limited in size to the maximum transfer size of that
149 transport. For Ethernet, this value is 1500 bytes. The
150 rpc_broadcast() function uses AUTH_SYS credentials by default (see
151 rpc_clnt_auth(3)).
152 rpc_broadcast_exp()
154 Like rpc_broadcast(), except that the initial timeout, inittime
155 and the maximum timeout, waittime are specified in milliseconds.
156 The inittime argument is the initial time that rpc_broadcast_exp()
157 waits before resending the request. After the first resend, the
158 re-transmission interval increases exponentially until it exceeds
159 waittime.
160 rpc_call()
162 Call the remote procedure associated with prognum, versnum, and
163 procnum on the machine, host. The inproc argument is used to
164 encode the procedure's arguments, and outproc is used to decode
165 the procedure's results; in is the address of the procedure's
166 argument(s), and out is the address of where to place the
167 result(s). The nettype argument can be any of the values listed
168 on rpc(3). This routine returns RPC_SUCCESS if it succeeds, or an
169 appropriate status is returned. Use the clnt_perrno() routine to
170 translate failure status into error messages. Warning: rpc_call()
171 uses the first available transport belonging to the class nettype,
172 on which it can create a connection. You do not have control of
173 timeouts or authentication using this routine.
174
176 These functions are part of libtirpc.
177
179 printf(3), rpc(3), rpc_clnt_auth(3), rpc_clnt_create(3)
180BSD May 7, 1993 BSD