XDefineCursor(3) Library Functions Manual XDefineCursor(3)

XDefineCursor, XUndefineCursor - define cursors

int XDefineCursor(Display *display, Window w, Cursor cursor);

int XUndefineCursor(Display *display, Window w);

cursor
Specifies the cursor that is to be displayed or None.
display
Specifies the connection to the X server.
w
Specifies the window.

If a cursor is set, it will be used when the pointer is in the window. If the cursor is None, it is equivalent to XUndefineCursor.

XDefineCursor can generate BadCursor and BadWindow errors.

The XUndefineCursor function undoes the effect of a previous XDefineCursor for this window. When the pointer is in the window, the parent's cursor will now be used. On the root window, the default cursor is restored.

XUndefineCursor can generate a BadWindow error.

BadAlloc
The server failed to allocate the requested resource or server memory.
BadCursor
A value for a Cursor argument does not name a defined Cursor.
BadWindow
A value for a Window argument does not name a defined Window.

XCreateFontCursor(3), XRecolorCursor(3)
Xlib - C Language X Interface
X Version 11 XLIB FUNCTIONS