DOKK / manpages / debian 11 / tk8.6-doc / Tk_Main.3tk.en
Tk_Main(3tk) Tk Library Procedures Tk_Main(3tk) 







Tk_Main - main program for Tk-based applications








#include <tk.h>

Tk_Main(argc, argv, appInitProc)









  
int argc (in)

  
Number of elements in argv.

  
char *argv[] (in)

  
Array of strings containing command-line arguments. On Windows, when using
      -DUNICODE, the parameter type changes to wchar_t *.

  
Tcl_AppInitProc *appInitProc (in)

  
Address of an application-specific initialization procedure. The value for
      this argument is usually Tcl_AppInit.
    
    

    

  










Tk_Main acts as the main program for most Tk-based
    applications. Starting with Tk 4.0 it is not called main anymore
    because it is part of the Tk library and having a function main in a
    library (particularly a shared library) causes problems on many systems.
    Having main in the Tk library would also make it hard to use Tk in
    C++ programs, since C++ programs must have special C++ main
    functions.


Normally each application contains a small main function
    that does nothing but invoke Tk_Main. Tk_Main then does all
    the work of creating and running a wish-like application.


When it is has finished its own initialization, but before it
    processes commands, Tk_Main calls the procedure given by the
    appInitProc argument. This procedure provides a “hook”
    for the application to perform its own initialization, such as defining
    application-specific commands. The procedure must have an interface that
    matches the type Tcl_AppInitProc:




typedef int Tcl_AppInitProc(


        Tcl_Interp *interp);



AppInitProc is almost always a pointer to Tcl_AppInit; for more
  details on this procedure, see the documentation for Tcl_AppInit.

Tk_Main functions much the same as Tcl_Main. In
    particular, Tk_Main supports both an interactive mode and a startup
    script mode, with the file name and encoding of a startup script under the
    control of the Tcl_SetStartupScript and Tcl_GetStartupScript
    routines. However it calls Tk_MainLoop after processing any supplied
    script, and in interactive uses events registered with
    Tcl_CreateFileHandler to process user input.








Tcl_DoOneEvent(3tk)








application-specific initialization, command-line arguments, main
    program







  

    4.0
    Tk