check for a fine poll() before it is used to sleep subsecond

2 files changed, 5 insertions, 2 deletions

diff --git a/src/config.h.in b/src/config.h.in
index ca36f2b3f..7c5a957db 100644
--- a/src/config.h.in
+++ b/src/config.h.in
@@ -35,6 +35,9 @@
 /* Define if you have the `poll' function. */
 #undef HAVE_POLL
 
+/* Define if you have a good `poll' function that can wait on NULL. */
+#undef HAVE_POLL_FINE
+
 /* Define if you can write to argc[] strings */
 #undef HAVE_WRITABLE_ARGV
 
diff --git a/src/main.c b/src/main.c
index 0a5624ba1..126fa4af0 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2243,7 +2243,7 @@ static void parseconfig(const char *filename,
 
 static void go_sleep(long ms)
 {
-#ifdef HAVE_POLL
+#ifdef HAVE_POLL_FINE
   /* portable subsecond "sleep" */
   poll((void *)0, 0, ms);
 #else
@@ -2259,7 +2259,7 @@ static void go_sleep(long ms)
   struct timeval timeout;
 
   timeout.tv_sec = ms/1000;
-  ms -= ms/1000;
+  ms = ms%1000;
   timeout.tv_usec = ms * 1000;
 
   select(0, NULL,  NULL, NULL, &timeout);