18.  Other Utility Functions  

(xlib-release-4-or-later?)

Returns always #t.

(xlib-release-5-or-later?)

Returns #t iff the Xlib extension is linked together with the X11 Release 5 Xlib or later versions of the Xlib.

(xlib-release-6-or-later?)

Returns #t iff the Xlib extension is linked together with the X11 Release 6 Xlib or later versions of the Xlib.

(get-default display program option)

See XGetDefault. program and option are strings or symbols. Returns a string of #f if the option does not exist for the specified program.

(resource-manager-string display)

See XResourceManagerString. Returns a string or #f if the RESOURCE_MANAGER property does not exist on the root window.

(parse-geometry string)

See XParseGeometry. Returns a list of six elements: two booleans indicating whether x or or y are negative and four integers (x, y, width, and height). Each of the elements can be #f to indicate that the respective value was not found in the string.

(parse-color colormap string)

See XParseColor. Returns an object of type color or #f if XParseColor fails.

(store-buffer display bytes buffer)

See XStoreBuffer. bytes is a string; buffer is an integer between 0 and 7.

(store-bytes display bytes)

See XStoreBytes. bytes is a string.

(fetch-buffer display buffer)

See XFetchBuffer. buffer is an integer between 0 and 7. Returns a string.

(fetch-bytes display)

See XFetchBytes. Returns a string.

(rotate-buffers display delta)

See XRotateBuffers. delta is an integer (the amount to rotate the buffers).

(with object . body-forms)

with is a macro. object must be a drawable, a graphics context, or a font. The body-forms are evaluated in order; with returns the value of the last body-form.

Within the scope of the with, the first call to an accessor function accessing object (such as window-attribute or font-attribute) causes the result of the corresponding Xlib function to be retained in a cache; subsequent calls just return the value from the cache. Likewise, calls to Xlib functions for mutator functions modifying object (such as set-window-attribute!) are delayed until exit of the with body or until an accessor function is called and the cached data for this accessor function has been invalidated by the call to a mutator function.


Markup created by unroff 1.0,    September 24, 1996,    net@informatik.uni-bremen.de