diff --git a/httplib.h b/httplib.h
index ca27295..649eb04 100644
--- a/httplib.h
+++ b/httplib.h
@@ -6014,12 +6014,6 @@ inline void calc_actual_timeout(time_t global_timeout_msec,
                                 time_t duration_msec, time_t timeout_sec,
                                 time_t timeout_usec, time_t &actual_timeout_sec,
                                 time_t &actual_timeout_usec) {
-  if (global_timeout_msec <= 0) {
-    actual_timeout_sec = timeout_sec;
-    actual_timeout_usec = timeout_usec;
-    return;
-  }
-
   auto timeout_msec = (timeout_sec * 1000) + (timeout_usec / 1000);
 
   auto actual_timeout_msec =
@@ -6045,6 +6039,10 @@ inline SocketStream::SocketStream(
 inline SocketStream::~SocketStream() = default;
 
 inline bool SocketStream::is_readable() const {
+  if (global_timeout_msec_ <= 0) {
+    return select_read(sock_, read_timeout_sec_, read_timeout_usec_) > 0;
+  }
+
   time_t read_timeout_sec;
   time_t read_timeout_usec;
   calc_actual_timeout(global_timeout_msec_, duration(), read_timeout_sec_,
@@ -9190,6 +9188,10 @@ inline SSLSocketStream::SSLSocketStream(
 inline SSLSocketStream::~SSLSocketStream() = default;
 
 inline bool SSLSocketStream::is_readable() const {
+  if (global_timeout_msec_ <= 0) {
+    return select_read(sock_, read_timeout_sec_, read_timeout_usec_) > 0;
+  }
+
   time_t read_timeout_sec;
   time_t read_timeout_usec;
   calc_actual_timeout(global_timeout_msec_, duration(), read_timeout_sec_,
diff --git a/test/test.cc b/test/test.cc
index a9621f3..f2b1089 100644
--- a/test/test.cc
+++ b/test/test.cc
@@ -8393,7 +8393,7 @@ TEST(GlobalTimeoutTest, ContentStreamSSL) {
   svr.wait_until_ready();
 
   const time_t timeout = 2000;
-  const time_t threshold = 500; // SSL_shutdown is slow...
+  const time_t threshold = 1000; // SSL_shutdown is slow...
 
   SSLClient cli("localhost", PORT);
   cli.enable_server_certificate_verification(false);