diff --git a/src/cmd/ksh93/bltins/sleep.c b/src/cmd/ksh93/bltins/sleep.c
index 15df5b1a7..aaf2f128b 100644
--- a/src/cmd/ksh93/bltins/sleep.c
+++ b/src/cmd/ksh93/bltins/sleep.c
@@ -139,7 +139,7 @@ void sh_delay(double t, int sflag)
 
 	ts.tv_sec = n;
 	ts.tv_nsec = 1000000000 * (t - (double)n);
-	while(tvsleep(&ts, &tx) < 0 && errno == EINTR)
+	while(tvsleep(&ts, &tx) < 0)
 	{
 		if ((shp->trapnote & (SH_SIGSET | SH_SIGTRAP)) || sflag)
 			return;
diff --git a/src/cmd/ksh93/tests/functions.sh b/src/cmd/ksh93/tests/functions.sh
index 2921f5d16..ecd0b218a 100755
--- a/src/cmd/ksh93/tests/functions.sh
+++ b/src/cmd/ksh93/tests/functions.sh
@@ -1126,7 +1126,7 @@ function gosleep
 	"$bin_sleep" 1
 }
 x=$(
-	(sleep .25; pid=; ps | grep sleep | read pid extra; [[ $pid ]] && kill -- "$pid") &
+	(sleep .25; pid=; ps 2>/dev/null | grep sleep | read pid extra; [[ $pid ]] && kill -- "$pid") &
 	gosleep 2> /dev/null
 	print ok
 )
diff --git a/src/cmd/ksh93/tests/variables.sh b/src/cmd/ksh93/tests/variables.sh
index 5309b04a9..136e4a173 100755
--- a/src/cmd/ksh93/tests/variables.sh
+++ b/src/cmd/ksh93/tests/variables.sh
@@ -40,11 +40,15 @@ if	(( RANDOM==RANDOM || $RANDOM==$RANDOM ))
 then	err_exit RANDOM variable not working
 fi
 # SECONDS
-let SECONDS=0.0
-sleep .001
-if	(( SECONDS < .001 ))
-then	err_exit "either 'sleep' or \$SECONDS not working"
+float secElapsed=0.0 secSleep=0.001
+let SECONDS=$secElapsed
+sleep $secSleep
+secElapsed=SECONDS
+if	(( secElapsed < secSleep ))
+then	err_exit "slept ${secElapsed} seconds instead of ${secSleep}: " \
+                 "either 'sleep' or \$SECONDS not working"
 fi
+unset -v secElapsed secSleep
 # _
 set abc def
 if	[[ $_ != def ]]
@@ -508,12 +512,11 @@ fi
 function foo
 {
 	typeset SECONDS=0
-	sleep .002
+	sleep 0.002
 	print $SECONDS
-
 }
 x=$(foo)
-(( x >.001 && x < 1 ))
+(( x >= 0.002 && x < 1 ))
 '
 } 2> /dev/null   || err_exit 'SECONDS not working in function'
 cat > $tmp/script <<-\!
diff --git a/src/lib/libast/tm/tvsleep.c b/src/lib/libast/tm/tvsleep.c
index 3a1b9aefe..5f65c3b52 100644
--- a/src/lib/libast/tm/tvsleep.c
+++ b/src/lib/libast/tm/tvsleep.c
@@ -41,6 +41,8 @@
 # endif
 #endif
 
+#define NANOSECONDS 1000000000L
+
 /*
  * sleep for tv
  * non-zero exit if sleep did not complete
@@ -53,11 +55,12 @@ int
 tvsleep(register const Tv_t* tv, register Tv_t* rv)
 {
 
+	int		r;
+
 #if _lib_nanosleep
 
 	struct timespec	stv;
 	struct timespec	srv;
-	int		r;
 
 	stv.tv_sec = tv->tv_sec;
 	stv.tv_nsec = tv->tv_nsec;
@@ -77,13 +80,11 @@ tvsleep(register const Tv_t* tv, register Tv_t* rv)
 
 #if _lib_select
 
-	struct timeval	stv;
+	struct timeval tvSleep = { tv->tv_sec, tv->tv_nsec / 1000 };
+	if (tv->tv_nsec % 1000)
+		++tvSleep.tv_usec;
 
-	stv.tv_sec = tv->tv_sec;
-	if (!(stv.tv_usec = tv->tv_nsec / 1000))
-		stv.tv_usec = 1;
-	if (select(0, NiL, NiL, NiL, &stv) >= 0)
-		return 0;
+	r = select(0, NiL, NiL, NiL, &tvSleep);
 
 #else
 
@@ -162,51 +163,52 @@ tvsleep(register const Tv_t* tv, register Tv_t* rv)
 
 	if (!(t = (n + 999999L) / 1000000L))
 		t = 1;
-	if (poll(&pfd, 0, t) >= 0)
-		return 0;
+	r = poll(&pfd, 0, t);
 
 #endif
 
 #endif
 
 	}
- bad:
-	if (errno == EINTR && rv)
+
+/* Ascertain whether we actually slept for a sufficient time.
+ * It is preferable to sleep a little more than necessary than too little.
+ */
 	{
-		tvgettime(rv);
-		if (rv->tv_nsec < bv.tv_nsec)
+		struct timespec tsAfter;
+		long sec, nsec;
+
+		tvgettime(&tsAfter);
+
+		/* Calculate seconds left to sleep */
+		sec = (long)(tv->tv_sec + tv->tv_nsec / NANOSECONDS) -
+			((long)tsAfter.tv_sec - (long)bv.tv_sec);
+
+		/* Calculate nanoseconds left to sleep */
+		nsec = (long)(tv->tv_nsec % NANOSECONDS) -
+			((long)tsAfter.tv_nsec - (long)bv.tv_nsec);
+		if (nsec >= NANOSECONDS)
 		{
-			rv->tv_nsec += 1000000000L;
-			rv->tv_sec--;
+			++sec;
+			nsec -= NANOSECONDS;
 		}
-		rv->tv_nsec -= bv.tv_nsec;
-		rv->tv_sec -= bv.tv_sec;
-		if (rv->tv_sec > tv->tv_sec)
+		else if (nsec < 0)
 		{
-			rv->tv_sec = 0;
-			rv->tv_nsec = 0;
+			--sec;
+			nsec += NANOSECONDS;
 		}
-		else
+
+		if (sec >= 0 && (sec > 0 || nsec > 0))
 		{
-			rv->tv_sec = tv->tv_sec - rv->tv_sec;
-			if (rv->tv_nsec > tv->tv_nsec)
+			if (rv)
 			{
-				if (!rv->tv_sec)
-				{
-					rv->tv_sec = 0;
-					rv->tv_nsec = 0;
-				}
-				else
-				{
-					rv->tv_sec--;
-					rv->tv_nsec = 1000000000L - rv->tv_nsec + tv->tv_nsec;
-				}
+				rv->tv_sec  = sec;
+				rv->tv_nsec = nsec;
 			}
-			else
-				rv->tv_nsec = tv->tv_nsec - rv->tv_nsec;
+			return -1;
 		}
 	}
-	return -1;
+	return r;
 
 #endif