spray(5tcp)

spray -- scatter data in order to check the network

Synopsis

#include <rpcsvc/spray.h>

Description

The spray protocol sends packets to a given machine to test the speed and reliability of communications with that machine.

The spray protocol is not a C function interface, per se, but can be accessed using the generic remote procedure calling interface clnt_call (see rpc_clnt_calls(3rpc)). The protocol sends a packet to the called host. The host acknowledges receipt of the packet. The protocol counts the number of acknowledgments and can return that count.

The spray protocol currently supports the following procedures, which should be called in the order given:

SPRAYPROC_CLEAR: This procedure clears the counter.
SPRAYPROC_SPRAY: This procedure sends the packet.
SPRAYPROC_GET: This procedure returns the count and the amount of time since the last SPRAYPROC_CLEAR.

The XDR routines xdr_sprayarr and xdr_spraycumul are available in librpcsvc.

References

rpc_clnt_calls(3rpc), spray(1Mtcp), sprayd(1Mtcp)

Examples

The following code fragment demonstrates how the spray protocol is used:

   #include <rpc/rpc.h>
   #include <rpcsvc/spray.h>
   ...
   spraycumul	spray_result;
   sprayarr	spray_data;
   char		buf[100];		/* arbitrary data */
   int		loop = 1000;
   CLIENT	*clnt;
   struct timeval timeout0 = {0, 0};
   struct timeval timeout25 = {25, 0};
   
   spray_data.sprayarr_len = (u_int)100;
   spray_data.sprayarr_val = buf;
   

   clnt = clnt_create("somehost", SPRAYPROG, SPRAYVERS, "netpath");
   if (clnt == (CLIENT *)NULL) {
   	/* handle this error */
   }
   

   if (clnt_call(clnt, SPRAYPROC_CLEAR,
   	xdr_void, NULL, xdr_void, NULL, timeout25)) {
   		/* handle this error */
   }
   while (loop-- > 0) {
   	if (clnt_call(clnt, SPRAYPROC_SPRAY,
   		xdr_sprayarr, &spray_data, xdr_void, NULL, timeout0)) {
   			/* handle this error */
   	}
   }
   if (clnt_call(clnt, SPRAYPROC_GET,
   	xdr_void, NULL, xdr_spraycumul, &spray_result, timeout25)) {
   		/* handle this error */
   }
   printf("Acknowledged %ld of 1000 packets in %d secs %d usecs\n",
   	spray_result.counter,
   	spray_result.clock.sec,
   	spray_result.clock.usec);