diff --git a/docs/api/mg_server_port.md b/docs/api/mg_server_port.md
index 01c9c42c..0159be8d 100644
--- a/docs/api/mg_server_port.md
+++ b/docs/api/mg_server_port.md
@@ -10,8 +10,8 @@
 |**`port`**|`int`|The port number on which the service listens|
 |**`is_ssl`**|`int`|**0** for `HTTP` communication, **1** for `HTTPS`|
 |**`is_redirect`**|`int`|**1** if all requests are redirected, otherwise **0**|
-|**`is_optional`**|`int`|**1** if prot is optional, otherwise **0**|
-|**`_reserved2`**|`int`|Reserved for internal use|
+|**`is_optional`**|`int`|**1** if port is optional, otherwise **0**|
+|**`is_bound`**|`int`|**1** if the port is bound, otherwise **0**|
 |**`_reserved3`**|`int`|Reserved for internal use|
 |**`_reserved4`**|`int`|Reserved for internal use|
 
diff --git a/include/civetweb.h b/include/civetweb.h
index 0b72eaf3..0ce344dc 100644
--- a/include/civetweb.h
+++ b/include/civetweb.h
@@ -715,7 +715,7 @@ struct mg_server_port {
 	int is_ssl;      /* https port: 0 = no, 1 = yes */
 	int is_redirect; /* redirect all requests: 0 = no, 1 = yes */
 	int is_optional; /* optional: 0 = no, 1 = yes */
-	int _reserved2;
+	int is_bound;    /* bound: 0 = no, 1 = yes, relevant for optional ports */
 	int _reserved3;
 	int _reserved4;
 };
diff --git a/src/civetweb.c b/src/civetweb.c
index 9f9ef2e8..2ee166cf 100644
--- a/src/civetweb.c
+++ b/src/civetweb.c
@@ -3338,6 +3338,7 @@ mg_get_server_ports(const struct mg_context *ctx,
 		ports[cnt].is_ssl = ctx->listening_sockets[i].is_ssl;
 		ports[cnt].is_redirect = ctx->listening_sockets[i].ssl_redir;
 		ports[cnt].is_optional = ctx->listening_sockets[i].is_optional;
+		ports[cnt].is_bound = ctx->listening_sockets[i].sock != INVALID_SOCKET;
 
 		if (ctx->listening_sockets[i].lsa.sa.sa_family == AF_INET) {
 			/* IPv4 */
diff --git a/unittest/public_server.c b/unittest/public_server.c
index bad2b77f..3ea5c45f 100644
--- a/unittest/public_server.c
+++ b/unittest/public_server.c
@@ -458,11 +458,13 @@ test_mg_start_stop_http_server_impl(int ipv6, int bound)
 	ck_assert_int_eq(portinfo[0].is_ssl, 0);
 	ck_assert_int_eq(portinfo[0].is_redirect, 0);
 	ck_assert_int_eq(portinfo[0].is_optional, 0);
+	ck_assert_int_eq(portinfo[0].is_bound, 0);
 	ck_assert_int_eq(portinfo[1].protocol, 0);
 	ck_assert_int_eq(portinfo[1].port, 0);
 	ck_assert_int_eq(portinfo[1].is_ssl, 0);
 	ck_assert_int_eq(portinfo[1].is_redirect, 0);
 	ck_assert_int_eq(portinfo[1].is_optional, 0);
+	ck_assert_int_eq(portinfo[1].is_bound, 0);
 
 	ret = mg_get_server_ports(ctx, 4, portinfo);
 	ck_assert_int_eq(ret, 1);
@@ -475,11 +477,13 @@ test_mg_start_stop_http_server_impl(int ipv6, int bound)
 	ck_assert_int_eq(portinfo[0].is_ssl, 0);
 	ck_assert_int_eq(portinfo[0].is_redirect, 0);
 	ck_assert_int_eq(portinfo[0].is_optional, 0);
+	ck_assert_int_eq(portinfo[0].is_bound, 1);
 	ck_assert_int_eq(portinfo[1].protocol, 0);
 	ck_assert_int_eq(portinfo[1].port, 0);
 	ck_assert_int_eq(portinfo[1].is_ssl, 0);
 	ck_assert_int_eq(portinfo[1].is_redirect, 0);
 	ck_assert_int_eq(portinfo[1].is_optional, 0);
+	ck_assert_int_eq(portinfo[1].is_bound, 0);
 
 	test_sleep(1);
 
@@ -679,11 +683,13 @@ START_TEST(test_mg_start_stop_https_server)
 	ck_assert_int_eq(portinfo[0].is_ssl, 0);
 	ck_assert_int_eq(portinfo[0].is_redirect, 0);
 	ck_assert_int_eq(portinfo[0].is_optional, 0);
+	ck_assert_int_eq(portinfo[0].is_bound, 0);
 	ck_assert_int_eq(portinfo[1].protocol, 0);
 	ck_assert_int_eq(portinfo[1].port, 0);
 	ck_assert_int_eq(portinfo[1].is_ssl, 0);
 	ck_assert_int_eq(portinfo[1].is_redirect, 0);
 	ck_assert_int_eq(portinfo[1].is_optional, 0);
+	ck_assert_int_eq(portinfo[1].is_bound, 0);
 
 	ret = mg_get_server_ports(ctx, 4, portinfo);
 	ck_assert_int_eq(ret, 2);
@@ -692,16 +698,19 @@ START_TEST(test_mg_start_stop_https_server)
 	ck_assert_int_eq(portinfo[0].is_ssl, 0);
 	ck_assert_int_eq(portinfo[0].is_redirect, 1);
 	ck_assert_int_eq(portinfo[0].is_optional, 0);
+	ck_assert_int_eq(portinfo[0].is_bound, 1);
 	ck_assert_int_eq(portinfo[1].protocol, 1);
 	ck_assert_int_eq(portinfo[1].port, 8443);
 	ck_assert_int_eq(portinfo[1].is_ssl, 1);
 	ck_assert_int_eq(portinfo[1].is_redirect, 0);
 	ck_assert_int_eq(portinfo[1].is_optional, 1);
+	ck_assert_int_eq(portinfo[1].is_bound, 1);
 	ck_assert_int_eq(portinfo[2].protocol, 0);
 	ck_assert_int_eq(portinfo[2].port, 0);
 	ck_assert_int_eq(portinfo[2].is_ssl, 0);
 	ck_assert_int_eq(portinfo[2].is_redirect, 0);
 	ck_assert_int_eq(portinfo[2].is_optional, 0);
+	ck_assert_int_eq(portinfo[2].is_bound, 0);
 
 	test_sleep(1);
 
@@ -810,16 +819,19 @@ START_TEST(test_mg_server_and_client_tls)
 	ck_assert_int_eq(ports[0].is_ssl, 0);
 	ck_assert_int_eq(ports[0].is_redirect, 1);
 	ck_assert_int_eq(ports[0].is_optional, 0);
+	ck_assert_int_eq(ports[0].is_bound, 1);
 	ck_assert_int_eq(ports[1].protocol, 1);
 	ck_assert_int_eq(ports[1].port, 8443);
 	ck_assert_int_eq(ports[1].is_ssl, 1);
 	ck_assert_int_eq(ports[1].is_redirect, 0);
 	ck_assert_int_eq(ports[1].is_optional, 1);
+	ck_assert_int_eq(ports[1].is_bound, 1);
 	ck_assert_int_eq(ports[2].protocol, 0);
 	ck_assert_int_eq(ports[2].port, 0);
 	ck_assert_int_eq(ports[2].is_ssl, 0);
 	ck_assert_int_eq(ports[2].is_redirect, 0);
 	ck_assert_int_eq(ports[2].is_optional, 0);
+	ck_assert_int_eq(ports[2].is_bound, 0);
 
 	test_sleep(1);