XParseGeometry

Section: XLIB FUNCTIONS (3)
Updated: libX11 1.6.4
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NAME

XParseGeometry, XWMGeometry - parse window geometry

SYNTAX

: int XParseGeometry(char *parsestring, int *x_return, int *y_return, unsigned int *width_return, unsigned int *height_return);
: int XWMGeometry(Display *display, int screen, char *user_geom, char *def_geom, unsigned int bwidth, XSizeHints *hints, int *x_return, int *y_return, int *width_return, int *height_return, int *gravity_return);

ARGUMENTS

position
default_position: Specify the geometry specifications.
display: Specifies the connection to the X server.
fheight
fwidth: Specify the font height and width in pixels (increment size).
parsestring: Specifies the string you want to parse.
screen: Specifies the screen.
width_return
height_return: Return the width and height determined.
xadder
yadder: Specify additional interior padding needed in the window.
x_return
y_return: Return the x and y offsets.
bwidth: Specifies the border width.
hints: Specifies the size hints for the window in its normal state.
def_geom: Specifies the application's default geometry or NULL.
gravity_return: Returns the window gravity.
user_geom: Specifies the user-specified geometry or NULL.

DESCRIPTION

By convention, X applications use a standard string to indicate window size and placement. XParseGeometry makes it easier to conform to this standard because it allows you to parse the standard window geometry. Specifically, this function lets you parse strings of the form:

[=][<width>{xX}<height>][{+-}<xoffset>{+-}<yoffset>]

The fields map into the arguments associated with this function. (Items enclosed in <> are integers, items in [] are optional, and items enclosed in {} indicate ``choose one of.'' Note that the brackets should not appear in the actual string.) If the string is not in the Host Portable Character Encoding, the result is implementation-dependent.

The XParseGeometry function returns a bitmask that indicates which of the four values (width, height, xoffset, and yoffset) were actually found in the string and whether the x and y values are negative. By convention, -0 is not equal to +0, because the user needs to be able to say ``position the window relative to the right or bottom edge.'' For each value found, the corresponding argument is updated. For each value not found, the argument is left unchanged. The bits are represented by XValue, YValue, WidthValue, HeightValue, XNegative, or YNegative and are defined in <X11/Xutil.h>. They will be set whenever one of the values is defined or one of the signs is set.

If the function returns either the XValue or YValue flag, you should place the window at the requested position.

The XWMGeometry function combines any geometry information (given in the format used by XParseGeometry) specified by the user and by the calling program with size hints (usually the ones to be stored in WM_NORMAL_HINTS) and returns the position, size, and gravity (NorthWestGravity, NorthEastGravity, SouthEastGravity, or SouthWestGravity) that describe the window. If the base size is not set in the XSizeHints structure, the minimum size is used if set. Otherwise, a base size of zero is assumed. If no minimum size is set in the hints structure, the base size is used. A mask (in the form returned by XParseGeometry) that describes which values came from the user specification and whether or not the position coordinates are relative to the right and bottom edges is returned. Note that these coordinates will have already been accounted for in the x_return and y_return values.

Note that invalid geometry specifications can cause a width or height of zero to be returned. The caller may pass the address of the hints win_gravity field as gravity_return to update the hints directly.