Volume One: Xlib Programming Manual - Niksula

Figure 13−2. R4 Procedure for processing resource specifications with resource manager functions
Routines that use these functions are shown and described in Chapter 14, "A Complete Application."
13.3 Standard Geometry
One of the preferences that must be handled by clients is the preferred size and placement of a window or icon. By
convention, rather than having the user specify various elements of the size and placement with separate options, clients
accept a single standard geometry string, which has the following format:
x{+−}{+−}
Items enclosed in are integers, and items enclosed in {} are a set from which one item is allowed. The xoffset and
yoffset values are optional. They determine the position of the window or icon−−for the top−level window, they are,
by convention, interpreted relative to the origin of the root window. The convention is that if the sign of xoffset or
yoffset is positive, they specify that the offset is measured from the top or left edge of the application window to the top
or left edge of the screen. If the sign of xoffset or yoffset is negative, they specify that the offset is measured from
the bottom or right edge of the application window to the bottom or right edge of the screen.
After being read in from the command line or from a preference file, this string can be separated into separate x, y,
width, and height values with XParseGeometry(). See Chapter 14, "A Complete Application "for an example
that uses XParseGeometry().
In addition, there is a function called XWMGeometry() that can be used to parse a partial geometry specification from the
user. XWMGeometry() takes a geometry string specified (presumably) by the user, which might not be complete, and the
set of size hints that define the programs desired geometry. If the user−specified string specifies an element of the
geometry, that value is used; otherwise, the corresponding value from program’s default geometry string is used. The