diff --git a/gio/gsocket.c b/gio/gsocket.c
index 3cdce1053..66832c15b 100644
--- a/gio/gsocket.c
+++ b/gio/gsocket.c
@@ -5750,6 +5750,13 @@ g_socket_receive_message (GSocket                 *socket,
  * the %G_IO_ERROR_NOT_SUPPORTED error. On Linux this is implemented
  * by reading the %SO_PEERCRED option on the underlying socket.
  *
+ * This method can be expected to be available on the following platforms:
+ *
+ * - Linux since GLib 2.26
+ * - OpenBSD since GLib 2.30
+ * - Solaris, Illumos and OpenSolaris since GLib 2.40
+ * - NetBSD since GLib 2.42
+ *
  * Other ways to obtain credentials from a foreign peer includes the
  * #GUnixCredentialsMessage type and
  * g_unix_connection_send_credentials() /
diff --git a/gio/gunixconnection.c b/gio/gunixconnection.c
index c85ac3650..e9e2f75f0 100644
--- a/gio/gunixconnection.c
+++ b/gio/gunixconnection.c
@@ -300,6 +300,14 @@ gboolean                g_unix_connection_create_pair                   (GUnixCo
  * byte to the stream, as this is required for credentials passing to
  * work on some implementations.
  *
+ * This method can be expected to be available on the following platforms:
+ *
+ * - Linux since GLib 2.26
+ * - FreeBSD since GLib 2.26
+ * - GNU/kFreeBSD since GLib 2.36
+ * - Solaris, Illumos and OpenSolaris since GLib 2.40
+ * - GNU/Hurd since GLib 2.40
+ *
  * Other ways to exchange credentials with a foreign peer includes the
  * #GUnixCredentialsMessage type and g_socket_get_credentials() function.
  *
@@ -450,6 +458,14 @@ g_unix_connection_send_credentials_finish (GUnixConnection *connection,
  * single byte from the stream, as this is required for credentials
  * passing to work on some implementations.
  *
+ * This method can be expected to be available on the following platforms:
+ *
+ * - Linux since GLib 2.26
+ * - FreeBSD since GLib 2.26
+ * - GNU/kFreeBSD since GLib 2.36
+ * - Solaris, Illumos and OpenSolaris since GLib 2.40
+ * - GNU/Hurd since GLib 2.40
+ *
  * Other ways to exchange credentials with a foreign peer includes the
  * #GUnixCredentialsMessage type and g_socket_get_credentials() function.
  *