diff --git a/doc/man/wl_display_connect.xml b/doc/man/wl_display_connect.xml
index 7e6e05c6..ded3cbd3 100644
--- a/doc/man/wl_display_connect.xml
+++ b/doc/man/wl_display_connect.xml
@@ -57,9 +57,8 @@
           that was previously opened by a Wayland server. The server socket must
           be placed in <envar>XDG_RUNTIME_DIR</envar> for this function to
           find it. The <varname>name</varname> argument specifies the name of
-          the socket or <constant>NULL</constant> to use the default (which is
-          <constant>"wayland-0"</constant>). The environment variable
-          <envar>WAYLAND_DISPLAY</envar> replaces the default value. If
+          the socket or <constant>NULL</constant> to use the default
+          (which is the value of <envar>WAYLAND_DISPLAY</envar>). If
           <envar>WAYLAND_SOCKET</envar> is set, this function behaves like
           <function>wl_display_connect_to_fd</function> with the file-descriptor
           number taken from the environment variable.</para>
diff --git a/doc/publican/sources/Protocol.xml b/doc/publican/sources/Protocol.xml
index 477063be..9464953b 100644
--- a/doc/publican/sources/Protocol.xml
+++ b/doc/publican/sources/Protocol.xml
@@ -60,10 +60,10 @@
     <title>Wire Format</title>
     <para>
       The protocol is sent over a UNIX domain stream socket, where the endpoint
-      usually is named <systemitem class="service">wayland-0</systemitem>
-      (although it can be changed via <emphasis>WAYLAND_DISPLAY</emphasis>
-      in the environment).  The protocol is message-based.  A
-      message sent by a client to the server is called request.  A message
+      name is determined by the <emphasis>WAYLAND_DISPLAY</emphasis>
+      environment variable.  Its value will usually be
+      <systemitem class="service">wayland-0</systemitem>.  The protocol is message-based.
+      A message sent by a client to the server is called request.  A message
       from the server to a client is called event.  Every message is
       structured as 32-bit words, values are represented in the host's
       byte-order.
diff --git a/src/wayland-client.c b/src/wayland-client.c
index 09c594ae..ffbca4b0 100644
--- a/src/wayland-client.c
+++ b/src/wayland-client.c
@@ -764,8 +764,11 @@ connect_to_socket(const char *name)
 
 	if (name == NULL)
 		name = getenv("WAYLAND_DISPLAY");
-	if (name == NULL)
-		name = "wayland-0";
+	if (name == NULL) {
+		wl_log("error: WAYLAND_DISPLAY not set in the environment.\n");
+		errno = ENOENT;
+		return -1;
+	}
 
 	fd = wl_os_socket_cloexec(PF_LOCAL, SOCK_STREAM, 0);
 	if (fd < 0)
@@ -869,8 +872,7 @@ wl_display_connect_to_fd(int fd)
  * \return A \ref wl_display object or \c NULL on failure
  *
  * Connect to the Wayland display named \c name. If \c name is \c NULL,
- * its value will be replaced with the WAYLAND_DISPLAY environment
- * variable if it is set, otherwise display "wayland-0" will be used.
+ * its value will be replaced with the WAYLAND_DISPLAY environment variable.
  *
  * \memberof wl_display
  */