XtOpenApplication, XtVaOpenApplication − initialize, open, or close a display


Widget XtOpenApplication(XtAppContext *app_context_return, String application_class, XrmOptionDescRec *options, Cardinal num_options, int *argc_in_out, String *argv_in_out, String *fallback_resources, WidgetClass widget_class, ArgList args, Cardinal num_args);

Widget XtVaOpenApplication(XtAppContext *app_context_return, String application_class, XrmOptionDescRec *options, Cardinal num_options, int *argc_in_out, String *argv_in_out, String *fallback_resources, WidgetClass widget_class, ...);



Specifies the application context.


Specifies the class name of this application, which usually is the generic name for all instances of this application.


Specifies how to parse the command line for any application-specific resources. The options argument is passed as a parameter to XrmParseCommand. For further information, see Xlib − C Language X Interface.


Specifies the number of entries in the options list.


Specifies a pointer to the number of command line parameters.


Specifies the command line parameters.


Specifies resource values to be used if the application class resource file cannot be opened or read, or NULL.


Specifies the widget class of the shell to be created.


Specifies the argument list to override any other resource specification for the created shell widget.


Specifies the number of entries in the argument list.


Specifies the variable argument list to override any other resource specification for the created shell widget.


The XtOpenApplication function calls XtToolkitInitialize followed by XtCreateApplicationContext, then calls XtOpenDisplay with display_string NULL and application_name NULL, and finally calls XtAppCreateShell with application_name NULL, the specified widget_class, and the specified args and num_args and returns the created shell. The modified argc and argv returned by XtDisplayInitialize are returned in argc_in_out and argv_in_out. If app_context_return is not NULL, the created application context is also returned. If the display specified by the command line cannot be opened, an error message is issued and XtOpenApplication terminates the application. If fallback_resources is non-NULL, XtAppSetFallbackResources is called with the value prior to calling XtOpenDisplay.

XtAppInitialize and XtVaAppInitialize have been superceded by XtOpenApplication and XtVaOpenApplication respectively.


XtAppInitialize(3Xt), XtVaAppInitialize(3Xt)
X Toolkit Intrinsics − C Language Interface
Xlib − C Language X Interface


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