diff --git a/src/xlib.rs b/src/xlib.rs
index f3d549a..6cc4aba 100644
--- a/src/xlib.rs
+++ b/src/xlib.rs
@@ -1165,6 +1165,50 @@ pub struct XClassHint {
     pub res_class: *mut c_char
 }
 
+bitflags! {
+    flags XSizeHintFlags: c_long {
+        const USPosition   = 0x00000001,
+        const USSize       = 0x00000002,
+        const PPosition    = 0x00000004,
+        const PSize        = 0x00000008,
+        const PMinSize     = 0x00000010,
+        const PMaxSize     = 0x00000020,
+        const PResizeInc   = 0x00000040,
+        const PAspect      = 0x00000080,
+        const PBaseSize    = 0x00000100,
+        const PWinGravity  = 0x00000200,
+        const PAllHints    =
+            PPosition.bits | PSize.bits |
+            PMinSize.bits | PMaxSize.bits | PResizeInc.bits | PAspect.bits
+    }
+}
+
+#[repr(C)]
+pub struct XSizeHintInternal {
+    pub x: c_int,
+    pub y: c_int
+}
+
+#[repr(C)]
+pub struct XSizeHints {
+    pub flags: XSizeHintFlags,
+    pub x: c_int,
+    pub y: c_int,
+    pub width: c_int,
+    pub height: c_int,
+    pub min_width: c_int,
+    pub min_height: c_int,
+    pub max_width: c_int,
+    pub max_height: c_int,
+    pub width_inc: c_int,
+    pub height_inc: c_int,
+    pub min_aspect: XSizeHintInternal,
+    pub max_aspect: XSizeHintInternal,
+    pub base_width: c_int,
+    pub base_height: c_int,
+    pub win_gravity: c_int
+}
+
 pub static ZPixmap: c_int = 2;  // depth == drawable depth
 
 #[link(name="X11")]
@@ -1596,6 +1640,8 @@ extern {
 
     pub fn XGetWindowAttributes(arg0: *mut Display, arg1: Window, arg2: *mut XWindowAttributes) -> c_int;
 
+    pub fn XGetWMNormalHints(arg0: *mut Display, arg1: Window, arg2: *mut XSizeHints, arg3: *mut c_long) -> c_int;
+
     pub fn XGrabButton(arg0: *mut Display, arg1: c_uint, arg2: c_uint, arg3: Window, arg4: c_int, arg5: c_uint, arg6: c_int, arg7: c_int, arg8: Window, arg9: Cursor) -> c_int;
 
     pub fn XGrabKey(arg0: *mut Display, arg1: c_int, arg2: c_uint, arg3: Window, arg4: c_int, arg5: c_int, arg6: c_int) -> c_int;