Creates a client handle for a remote program using the specified class of transport within the specified timeout.
Network Services Library (libnsl.a)
#include <rpc/rpc.h>
CLIENT * clnt_tp_create_timed(host, prognum, versnum, nconf, timeout)
const char *host;
const rpcprog_t prognum;
const rpcvers_t versnum;
const struct netconfig *nconf;
const struct timeval *timeout;
The clnt_tp_create_timed subroutine is an intermediate level API. The subroutine enables the application to have a better control over the transport service to be used. The subroutine creates a client handle for the specified program and version. This client handle is created and returned from the remote host where server is located. The operation is done with a transport service specified by nconf parameter. The service can be a connection-oriented or connectionless service. The timeout parameter specifies the time duration within which the subroutine returns. If the timeout value expires, the subroutine fails and returns NULL.
Item | Description |
---|---|
host | Specifies the host name where the server resides. |
prognum | Specifies the program number of the remote program. |
versnum | Specifies the version number of the remote program. |
nconf | Defines a specific transport service to use. |
timeout | Specifies the timeout value. |
Item | Description |
---|---|
a generic client handle that is valid | successful |
NULL | unsuccessful |
You can use the clnt_pcreateerror subroutine to obtain the reason for failure.
Item | Description |
---|---|
RPC_UNKNOWNPROTO |
|
RPC_UNKNOWNHOST | The host name is not valid. |
RPC_TLIERROR | The value of the nconf parameter is set to udp and a call to the clnt_tp_create subroutine is made from the client program with nconf member (nc_semantics = NC_TPI_COTS_ORD). |
RPC_PROGNOTREGISTERED | The program number is not valid. |
RPC_TIMEDOUT | The timeout value has expired. |
In the following example, the clnt_tp_create_timed subroutine returns a generic client handle using the tcp transport service on successful completion. If the timeout value expires, the subroutine returns NULL.
#include <stdlib.h>
#include <rpc/rpc.h>
int main()
{
CLIENT *client;
struct netconfig *nconf;
char hostname[255]; /* The Remote host where server is located */
rpcprog_t PROGNUM = 0x3fffffffL;
rpcvers_t PROGVER = 0x1L;
const struct timeval timeout = { 25 , 0 } ;
/* getnetconfigent() returns a pointer to the struct netconfig
* structure corresponding to tcp transport
*/
if ((nconf = getnetconfigent("tcp")) == (struct netconfig *)NULL)
{
fprintf(stderr, "Cannot get netconfig entry for UDP\n");
exit(2);
}
client = clnt_tp_create_timed(hostname, PROGNUM, PROGVER, nconf, &timeout);
if (client == (CLIENT *)NULL)
{
fprintf(stderr,"Couldn't create client at inter lvl\n");
clnt_pcreateerror("Inter lvl : ");
exit(EXIT_FAILURE);
}
/*
* Make a call to clnt_call() subroutine
*/
/* Destroy client handle in the end */
clnt_destroy(client);
return 0 ;
}