XCreateGlyphCursor can generate BadAlloc , BadFont , and BadValue errors. The server failed to allocate the requested resource or server memory. BadFont A value for a Font or GContext argument does not name a defined Font. Some argument or pair of arguments has the correct type and range but fails to match in some other way required by the request. A value for a Pixmap argument does not name a defined Pixmap.
Some numeric value falls outside the range of values accepted by the request.
Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can generate this error.