1 files changed, 1 insertions, 1 deletions
diff --git a/test/threads.cxx b/test/threads.cxx
index 68370d246..f7349a668 100644
--- a/test/threads.cxx
+++ b/test/threads.cxx
@@ -73,7 +73,7 @@ extern "C" void* prime_func(void* p)
     for (pp=3; pp<=hn; pp+=2) if ( n%pp == 0 ) break;
     if (pp >= hn) {
       char s[128];
-      sprintf(s, "%d", n);
+      snprintf(s, 128, "%d", n);
 
       // Obtain a lock before we access the browser widget...
       Fl::lock();