Index: src/backend/postmaster/pgstat.c
===================================================================
RCS file: /projects/cvsroot/pgsql-server/src/backend/postmaster/pgstat.c,v
retrieving revision 1.61
diff -c -r1.61 pgstat.c
*** src/backend/postmaster/pgstat.c	15 Mar 2004 16:21:37 -0000	1.61
--- src/backend/postmaster/pgstat.c	21 Mar 2004 16:41:23 -0000
***************
*** 191,196 ****
--- 191,199 ----
  			   *addr,
  				hints;
  	int			ret;
+ 	fd_set      rset;
+ 	struct timeval tv;
+ 	char        test_byte;
  
  	/*
  	 * Force start of collector daemon if something to collect
***************
*** 307,312 ****
--- 310,351 ----
  			pgStatSock = -1;
  			continue;
  		}
+ 
+ #define TESTBYTEVAL 99
+ 
+ 		/* try to send and receive a test byte on the socket */
+ 
+ 		FD_ZERO(&rset);
+ 		FD_SET(pgStatSock, &rset);
+ 		tv.tv_sec = 0;
+ 		tv.tv_usec = 500000;
+ 		test_byte = TESTBYTEVAL;
+ 		send(pgStatSock,&test_byte,1,0);
+ 		test_byte++;
+ 		if(select(pgStatSock+1,&rset,NULL,NULL,&tv) > 0 && 
+ 		   FD_ISSET(pgStatSock,&rset))
+ 		{
+ 			recv(pgStatSock,&test_byte,1,0);
+ 			if(test_byte != TESTBYTEVAL)
+ 			{
+ 				ereport(LOG,
+ 						(errcode_for_socket_access(),
+ 						 errmsg("incorrect test value on send/receive on socket for statistics collector: %m")));
+ 			closesocket(pgStatSock);
+ 			pgStatSock = -1;
+ 			continue;
+ 			}
+ 		}
+ 		else
+ 		{
+ 			ereport(LOG,
+ 					(errcode_for_socket_access(),
+ 					 errmsg("could send/receive on socket for statistics collector: %m")));
+ 			closesocket(pgStatSock);
+ 			pgStatSock = -1;
+ 			continue;
+ 		}
+ 		
  
  		/* If we get here, we have a working socket */
  		break;