XAllocClassHint(3X11X Version 11 (Release 6.XAllocClassHint(3X11)
NAME
XAllocClassHint, XSetClassHint, XGetClassHint, XClassHint -
allocate class hints structure and set or read a window's
WM_CLASS property
SYNTAX
XClassHint *XAllocClassHint()
XSetClassHint(display, w, class_hints)
Display *display;
Window w;
XClassHint *class_hints;
Status XGetClassHint(display, w, class_hints_return)
Display *display;
Window w;
XClassHint *class_hints_return;
ARGUMENTS
display Specifies the connection to the X server.
class_hints
Specifies the XClassHint structure that is to be
used.
class_hints_return
Returns the XClassHint structure.
w Specifies the window.
DESCRIPTION
The XAllocClassHint function allocates and returns a pointer
to a XClassHint structure. Note that the pointer fields in
the XClassHint structure are initially set to NULL. If
insufficient memory is available, XAllocClassHint returns
NULL. To free the memory allocated to this structure, use
XFree.
The XSetClassHint function sets the class hint for the
specified window. If the strings are not in the Host
Portable Character Encoding, the result is implementation-
dependent.
XSetClassHint can generate BadAlloc and BadWindow errors.
The XGetClassHint function returns the class hint of the
specified window to the members of the supplied structure.
If the data returned by the server is in the Latin Portable
Character Encoding, then the returned strings are in the
Host Portable Character Encoding. Otherwise, the result is
implementation-dependent. It returns a nonzero status on
success; otherwise, it returns a zero status. To free
Page 1 (printed 7/20/06)
XAllocClassHint(3X11X Version 11 (Release 6.XAllocClassHint(3X11)
res_name and res_class when finished with the strings, use
XFree on each individually.
XGetClassHint can generate a BadWindow error.
PROPERTIES
WM_CLASS Set by application programs to allow window and
session managers to obtain the application's
resources from the resource database.
STRUCTURES
The XClassHint structure contains:
typedef struct {
char *res_name;
char *res_class;
} XClassHint;
The res_name member contains the application name, and the
res_class member contains the application class. Note that
the name set in this property may differ from the name set
as WM_NAME. That is, WM_NAME specifies what should be
displayed in the title bar and, therefore, can contain
temporal information (for example, the name of a file
currently in an editor's buffer). On the other hand, the
name specified as part of WM_CLASS is the formal name of the
application that should be used when retrieving the
application's resources from the resource database.
DIAGNOSTICS
BadAlloc The server failed to allocate the requested
resource or server memory.
BadWindow A value for a Window argument does not name a
defined Window.
SEE ALSO
XAllocIconSize(3X11), XAllocSizeHints(3X11),
XAllocWMHints(3X11), XFree(3X11), XSetCommand(3X11),
XSetTransientForHint(3X11), XSetTextProperty(3X11),
XSetWMClientMachine(3X11), XSetWMColormapWindows(3X11),
XSetWMIconName(3X11), XSetWMName(3X11),
XSetWMProperties(3X11), XSetWMProtocols(3X11),
XStringListToTextProperty(3X11)
Xlib - C Language X Interface
Page 2 (printed 7/20/06)
