1RPC_CLNT_CREATE(3) BSD Library Functions Manual RPC_CLNT_CREATE(3)
2
4 rpc_clnt_create, clnt_control, clnt_create, clnt_create_timed,
5 clnt_create_vers, clnt_create_vers_timed, clnt_destroy, clnt_dg_create,
6 clnt_pcreateerror, clnt_raw_create, clnt_spcreateerror, clnt_tli_create,
7 clnt_tp_create, clnt_tp_create_timed, clnt_vc_create, rpc_createerr —
8 library routines for dealing with creation and manipulation of CLIENT
9 handles
10
12 Standard C Library (libc, -lc)
13
15 #include <rpc/rpc.h>
16 bool_t
18 clnt_control(CLIENT *clnt, const u_int req, char *info);
19 CLIENT *
21 clnt_create(const char * host, const rpcprog_t prognum,
22 const rpcvers_t versnum, const char *nettype);
23 CLIENT *
25 clnt_create_timed(const char * host, const rpcprog_t prognum,
26 const rpcvers_t versnum, const char *nettype,
27 const struct timeval *timeout);
28 CLIENT *
30 clnt_create_vers(const char * host, const rpcprog_t prognum,
31 rpcvers_t *vers_outp, const rpcvers_t vers_low,
32 const rpcvers_t vers_high, const char *nettype);
33 CLIENT *
35 clnt_create_vers_timed(const char * host, const rpcprog_t prognum,
36 rpcvers_t *vers_outp, const rpcvers_t vers_low,
37 const rpcvers_t vers_high, char *nettype,
38 const struct timeval *timeout);
39 void
41 clnt_destroy(CLIENT *clnt);
42 CLIENT *
44 clnt_dg_create(const int fildes, const struct netbuf *svcaddr,
45 const rpcprog_t prognum, const rpcvers_t versnum, const u_int sendsz,
46 const u_int recvsz);
47 void
49 clnt_pcreateerror(const char *s);
50 char *
52 clnt_spcreateerror(const char *s);
53 CLIENT *
55 clnt_raw_create(const rpcprog_t prognum, const rpcvers_t versnum);
56 CLIENT *
58 clnt_tli_create(const int fildes, const struct netconfig *netconf,
59 const struct netbuf *svcaddr, const rpcprog_t prognum,
60 const rpcvers_t versnum, const u_int sendsz, const u_int recvsz);
61 CLIENT *
63 clnt_tp_create(const char * host, const rpcprog_t prognum,
64 const rpcvers_t versnum, const struct netconfig *netconf);
65 CLIENT *
67 clnt_tp_create_timed(const char * host, const rpcprog_t prognum,
68 const rpcvers_t versnum, const struct netconfig *netconf,
69 const struct timeval *timeout);
70 CLIENT *
72 clnt_vc_create(const int fildes, const struct netbuf *svcaddr,
73 const rpcprog_t prognum, const rpcvers_t versnum, u_int sendsz,
74 u_int recvsz);
75
77 RPC library routines allow C language programs to make procedure calls on
78 other machines across the network. First a CLIENT handle is created and
79 then the client calls a procedure to send a request to the server. On
80 receipt of the request, the server calls a dispatch routine to perform
81 the requested service, and then sends a reply.
82
84 clnt_control()
85 A function macro to change or retrieve various information about
86 a client object. The req argument indicates the type of opera‐
87 tion, and info is a pointer to the information. For both con‐
88 nectionless and connection-oriented transports, the supported
89 values of req and their argument types and what they do are:
90 CLSET_TIMEOUT struct timeval * set total timeout
92 CLGET_TIMEOUT struct timeval * get total timeout
93 Note: if you set the timeout using clnt_control(), the timeout
95 argument passed by clnt_call() is ignored in all subsequent
96 calls.
97 Note: If you set the timeout value to 0, clnt_control() immedi‐
99 ately returns an error (RPC_TIMEDOUT). Set the timeout argument
100 to 0 for batching calls.
101 CLGET_SVC_ADDR struct netbuf * get servers address
103 CLGET_FD int * get fd from handle
104 CLSET_FD_CLOSE void close fd on destroy
105 CLSET_FD_NCLOSE void don't close fd on destroy
106 CLGET_VERS u_int32_t * get RPC program version
107 CLSET_VERS u_int32_t * set RPC program version
108 CLGET_XID u_int32_t * get XID of previous call
109 CLSET_XID u_int32_t * set XID of next call
110 The following operations are valid for connectionless transports
112 only:
113 CLSET_RETRY_TIMEOUT struct timeval * set the retry timeout
115 CLGET_RETRY_TIMEOUT struct timeval * get the retry timeout
116 CLSET_CONNECT int * use connect(2)
117 The retry timeout is the time that RPC waits for the server to
119 reply before retransmitting the request. The clnt_control()
120 function returns TRUE on success and FALSE on failure.
121 clnt_create()
123 Generic client creation routine for program prognum and version
124 versnum. The host argument identifies the name of the remote
125 host where the server is located. The nettype argument indi‐
126 cates the class of transport protocol to use. The transports
127 are tried in left to right order in NETPATH environment variable
128 or in top to bottom order in the netconfig database. The
129 clnt_create() function tries all the transports of the nettype
130 class available from the NETPATH environment variable and the
131 netconfig database, and chooses the first successful one. A
132 default timeout is set and can be modified using clnt_control().
133 This routine returns NULL if it fails. The clnt_pcreateerror()
134 routine can be used to print the reason for failure.
135 Note: clnt_create() returns a valid client handle even if the
137 particular version number supplied to clnt_create() is not reg‐
138 istered with the rpcbind(8) service. This mismatch will be dis‐
139 covered by a clnt_call() later (see rpc_clnt_calls(3)).
140 clnt_create_timed()
142 Generic client creation routine which is similar to
143 clnt_create() but which also has the additional argument timeout
144 that specifies the maximum amount of time allowed for each
145 transport class tried. In all other respects, the
146 clnt_create_timed() call behaves exactly like the clnt_create()
147 call.
148 clnt_create_vers()
150 Generic client creation routine which is similar to
151 clnt_create() but which also checks for the version availabil‐
152 ity. The host argument identifies the name of the remote host
153 where the server is located. The nettype argument indicates the
154 class transport protocols to be used. If the routine is suc‐
155 cessful it returns a client handle created for the highest ver‐
156 sion between vers_low and vers_high that is supported by the
157 server. The vers_outp argument is set to this value. That is,
158 after a successful return vers_low <= *vers_outp <= vers_high.
159 If no version between vers_low and vers_high is supported by the
160 server then the routine fails and returns NULL. A default time‐
161 out is set and can be modified using clnt_control(). This rou‐
162 tine returns NULL if it fails. The clnt_pcreateerror() routine
163 can be used to print the reason for failure. Note:
164 clnt_create() returns a valid client handle even if the particu‐
165 lar version number supplied to clnt_create() is not registered
166 with the rpcbind(8) service. This mismatch will be discovered
167 by a clnt_call() later (see rpc_clnt_calls(3)). However,
168 clnt_create_vers() does this for you and returns a valid handle
169 only if a version within the range supplied is supported by the
170 server.
171 clnt_create_vers_timed()
173 Generic client creation routine which is similar to
174 clnt_create_vers() but which also has the additional argument
175 timeout that specifies the maximum amount of time allowed for
176 each transport class tried. In all other respects, the
177 clnt_create_vers_timed() call behaves exactly like the
178 clnt_create_vers() call.
179 clnt_destroy()
181 A function macro that destroys the client's RPC handle.
182 Destruction usually involves deallocation of private data struc‐
183 tures, including clnt itself. Use of clnt is undefined after
184 calling clnt_destroy(). If the RPC library opened the associ‐
185 ated file descriptor, or CLSET_FD_CLOSE was set using
186 clnt_control(), the file descriptor will be closed. The caller
187 should call auth_destroy(clnt->cl_auth) (before calling
188 clnt_destroy()) to destroy the associated AUTH structure (see
189 rpc_clnt_auth(3)).
190 clnt_dg_create()
192 This routine creates an RPC client for the remote program
193 prognum and version versnum; the client uses a connectionless
194 transport. The remote program is located at address svcaddr.
195 The fildes argument is an open and bound file descriptor. This
196 routine will resend the call message in intervals of 15 seconds
197 until a response is received or until the call times out. The
198 total time for the call to time out is specified by clnt_call()
199 (see clnt_call() in rpc_clnt_calls(3)). The retry time out and
200 the total time out periods can be changed using clnt_control().
201 The user may set the size of the send and receive buffers with
202 the sendsz and recvsz arguments; values of 0 choose suitable
203 defaults. This routine returns NULL if it fails.
204 clnt_pcreateerror()
206 Print a message to standard error indicating why a client RPC
207 handle could not be created. The message is prepended with the
208 string s and a colon, and appended with a newline.
209 clnt_spcreateerror()
211 Like clnt_pcreateerror(), except that it returns a string
212 instead of printing to the standard error. A newline is not
213 appended to the message in this case. Warning: returns a
214 pointer to a buffer that is overwritten on each call.
215 clnt_raw_create()
217 This routine creates an RPC client handle for the remote program
218 prognum and version versnum. The transport used to pass mes‐
219 sages to the service is a buffer within the process's address
220 space, so the corresponding RPC server should live in the same
221 address space; (see svc_raw_create() in rpc_svc_create(3)).
222 This allows simulation of RPC and measurement of RPC overheads,
223 such as round trip times, without any kernel or networking
224 interference. This routine returns NULL if it fails. The
225 clnt_raw_create() function should be called after
226 svc_raw_create().
227 clnt_tli_create()
229 This routine creates an RPC client handle for the remote program
230 prognum and version versnum. The remote program is located at
231 address svcaddr. If svcaddr is NULL and it is connection-ori‐
232 ented, it is assumed that the file descriptor is connected. For
233 connectionless transports, if svcaddr is NULL, RPC_UNKNOWNADDR
234 error is set. The fildes argument is a file descriptor which
235 may be open, bound and connected. If it is RPC_ANYFD, it opens
236 a file descriptor on the transport specified by netconf. If
237 fildes is RPC_ANYFD and netconf is NULL, a RPC_UNKNOWNPROTO
238 error is set. If fildes is unbound, then it will attempt to
239 bind the descriptor. The user may specify the size of the buf‐
240 fers with the sendsz and recvsz arguments; values of 0 choose
241 suitable defaults. Depending upon the type of the transport
242 (connection-oriented or connectionless), clnt_tli_create() calls
243 appropriate client creation routines. This routine returns NULL
244 if it fails. The clnt_pcreateerror() routine can be used to
245 print the reason for failure. The remote rpcbind service (see
246 rpcbind(8)) is not consulted for the address of the remote ser‐
247 vice.
248 clnt_tp_create()
250 Like clnt_create() except clnt_tp_create() tries only one trans‐
251 port specified through netconf. The clnt_tp_create() function
252 creates a client handle for the program prognum, the version
253 versnum, and for the transport specified by netconf. Default
254 options are set, which can be changed using clnt_control()
255 calls. The remote rpcbind service on the host host is consulted
256 for the address of the remote service. This routine returns
257 NULL if it fails. The clnt_pcreateerror() routine can be used
258 to print the reason for failure.
259 clnt_tp_create_timed()
261 Like clnt_tp_create() except clnt_tp_create_timed() has the
262 extra argument timeout which specifies the maximum time allowed
263 for the creation attempt to succeed. In all other respects, the
264 clnt_tp_create_timed() call behaves exactly like the
265 clnt_tp_create() call.
266 clnt_vc_create()
268 This routine creates an RPC client for the remote program
269 prognum and version versnum; the client uses a connection-ori‐
270 ented transport. The remote program is located at address
271 svcaddr. The fildes argument is an open and bound file descrip‐
272 tor. The user may specify the size of the send and receive buf‐
273 fers with the sendsz and recvsz arguments; values of 0 choose
274 suitable defaults. This routine returns NULL if it fails. The
275 address svcaddr should not be NULL and should point to the
276 actual address of the remote program. The clnt_vc_create()
277 function does not consult the remote rpcbind service for this
278 information.
279 struct rpc_createerr rpc_createerr;
281 A global variable whose value is set by any RPC client handle
282 creation routine that fails. It is used by the routine
283 clnt_pcreateerror() to print the reason for the failure.
284
286 rpc(3), rpc_clnt_auth(3), rpc_clnt_calls(3), rpcbind(8)
287BSD May 7, 1993 BSD