potential bug in David Brownell's zcip code

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--- zcip.c.orig	2004-12-20 17:09:12.000000000 +0100
+++ zcip.c	2004-12-22 10:29:02.717064544 +0100
@@ -369,28 +369,28 @@
 	//  - use it
 	//  - defend it, within limits
 	while (1) {
-		struct pollfd fds[1];
-		struct timeval tv1;
+		fd_set rfds, efds;
+		struct timeval to, *pto;
 
-		fds[0].fd = fd;
-		fds[0].events = POLLIN | POLLERR;
-		fds[0].revents = 0;
+		FD_ZERO(&rfds);
+		FD_SET(fd, &rfds);
+		FD_ZERO(&efds);
+		FD_SET(fd, &efds);
 
 		// poll, being ready to adjust current timeout 
-		if (timeout > 0) {
-			gettimeofday(&tv1, NULL);
-			tv1.tv_usec += (timeout % 1000) * 1000;
-			if (tv1.tv_usec > 1000000) {
-				tv1.tv_usec -= 1000000;
-				tv1.tv_sec++;
-			}
-			tv1.tv_sec += timeout / 1000;
-		} else if (timeout == 0) {
+		if (timeout == 0) {
 			timeout = ms_rdelay(PROBE_WAIT);
 		}
 		VDBG("...wait %ld %s nprobes=%d, nclaims=%d\n",
 				timeout, intf, nprobes, nclaims);
-		switch (poll(fds, 1, timeout)) {
+		if (timeout == -1)
+			pto = NULL;
+		else {
+			to.tv_sec = timeout / 1000;
+			to.tv_usec = (timeout % 1000) * 1000;
+			pto = &to;
+		}
+		switch (select(fd + 1, &rfds, NULL, &efds, pto)) {
 
 		// timeouts trigger protocol transitions
 		case 0:
@@ -437,19 +437,10 @@
 		case 1:
 			// maybe adjust timeout
 			if (timeout > 0) {
-				struct timeval tv2;
-
-				gettimeofday(&tv2, NULL);
-				if (timercmp(&tv1, &tv2, <)) {
-					timeout = -1;
-				} else {
-					timersub(&tv1, &tv2, &tv1);
-					timeout = 1000 * tv1.tv_sec
-							+ tv1.tv_usec / 1000;
-				}
+				timeout = to.tv_sec * 1000 + to.tv_usec / 1000;
 			}
-			if ((fds[0].revents & POLLIN) == 0) {
-				if (fds[0].revents & POLLERR) {
+			if (FD_ISSET(fd, &rfds) == 0) {
+				if (FD_ISSET(fd, &efds) != 0) {
 					// FIXME: links routinely go down;
 					// this shouldn't necessarily exit.
 					fprintf(stderr, "%s %s: poll error\n",

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