diff --git a/Modules/timemodule.c b/Modules/timemodule.c
--- a/Modules/timemodule.c
+++ b/Modules/timemodule.c
@@ -915,23 +915,28 @@ floatsleep(double secs)
 #if defined(HAVE_SELECT) && !defined(__EMX__)
     struct timeval t;
     double frac;
+    int err;
+
     frac = fmod(secs, 1.0);
     secs = floor(secs);
     t.tv_sec = (long)secs;
     t.tv_usec = (long)(frac*1000000.0);
     Py_BEGIN_ALLOW_THREADS
-    if (select(0, (fd_set *)0, (fd_set *)0, (fd_set *)0, &t) != 0) {
+    err = select(0, (fd_set *)0, (fd_set *)0, (fd_set *)0, &t);
+    Py_END_ALLOW_THREADS
+    if (err) {
+        if (PyErr_CheckSignals())
+            return -1;
 #ifdef EINTR
-        if (errno != EINTR) {
+        if (errno != EINTR)
 #else
-        if (1) {
+        if (1)
 #endif
-            Py_BLOCK_THREADS
+        {
             PyErr_SetFromErrno(PyExc_IOError);
             return -1;
         }
     }
-    Py_END_ALLOW_THREADS
 #elif defined(__WATCOMC__) && !defined(__QNX__)
     /* XXX Can't interrupt this sleep */
     Py_BEGIN_ALLOW_THREADS
@@ -941,6 +946,7 @@ floatsleep(double secs)
     {
         double millisecs = secs * 1000.0;
         unsigned long ul_millis;
+        int interrupted;
 
         if (millisecs > (double)ULONG_MAX) {
             PyErr_SetString(PyExc_OverflowError,
@@ -953,8 +959,10 @@ floatsleep(double secs)
          */
         ul_millis = (unsigned long)millisecs;
         if (ul_millis == 0 ||
-            main_thread != PyThread_get_thread_ident())
-            Sleep(ul_millis);
+            main_thread != PyThread_get_thread_ident()) {
+            Sleep(0);
+            interrupted = 0;
+        }
         else {
             DWORD rc;
             ResetEvent(hInterruptEvent);
@@ -964,13 +972,17 @@ floatsleep(double secs)
                  * handler called.
                  */
                 Sleep(1);
-                Py_BLOCK_THREADS
-                errno = EINTR;
-                PyErr_SetFromErrno(PyExc_IOError);
-                return -1;
+                interrupted = 1;
             }
         }
         Py_END_ALLOW_THREADS
+        if (interrupted) {
+            if (PyErr_CheckSignals())
+                return -1;
+            errno = EINTR;
+            PyErr_SetFromErrno(PyExc_IOError);
+            return -1;
+        }
     }
 #elif defined(PYOS_OS2)
     /* This Sleep *IS* Interruptable by Exceptions */