## Tcl8.6.0/Tk8.6.0 Documentation > Tk C API, version 8.6.0 > TkInitStubs

### Tcl/Tk Applications | Tcl Commands | Tk Commands | [incr Tcl] Package Commands | SQLite Package Commands | TDBC Package Commands | tdbc::mysql Package Commands | tdbc::odbc Package Commands | tdbc::postgres Package Commands | tdbc::sqlite3 Package Commands | Thread Package Commands | Tcl C API | Tk C API | [incr Tcl] Package C API | TDBC Package C API

  NAME
    Tk_InitStubs — initialize the Tk stubs mechanism
  SYNOPSIS
    #include <tk8.6/tk.h>
    const char *
    Tk_InitStubs(interp, version, exact)
  ARGUMENTS
  INTRODUCTION
  DESCRIPTION
  SEE ALSO
  KEYWORDS

### NAME

Tk_InitStubs — initialize the Tk stubs mechanism

### SYNOPSIS

#include <tk8.6/tk.h>
const char *
Tk_InitStubs(interp, version, exact)

### ARGUMENTS

Tcl_Interp *interp (in)
  Tcl interpreter handle.

char *version (in)
  A version string consisting of one or more decimal numbers separated by dots.

int exact (in)
  Non-zero means that only the particular Tk version specified by version is acceptable. Zero means that versions newer than version are also acceptable as long as they have the same major version number as version.

### INTRODUCTION

The Tcl stubs mechanism defines a way to dynamically bind extensions to a particular Tcl implementation at run time. the stubs mechanism requires no changes to applications incorporating Tcl/Tk interpreters. Only developers creating C-based Tcl/Tk extensions need to take steps to use the stubs mechanism with their extensions. See the Tcl_InitStubs page for more information.

Enabling the stubs mechanism for a Tcl/Tk extension requires the following steps:

1. Call Tcl_InitStubs in the extension before calling any other Tcl functions.

2. Call Tk_InitStubs if the extension before calling any other Tk functions.

3. Define the USE_TCL_STUBS and the USE_TK_STUBS symbols. Typically, you would include the -DUSE_TCL_STUBS and the -DUSE_TK_STUBS flags when compiling the extension.

4. Link the extension with the Tcl and Tk stubs libraries instead of the standard Tcl and Tk libraries. On Unix platforms, the library names are libtclstub8.4.a and libtkstub8.4.a; on Windows platforms, the library names are tclstub84.lib and tkstub84.lib. Adjust the library names with appropriate version number but note that the extension may only be used with versions of Tcl/Tk that have that version number or higher.

### DESCRIPTION

Tk_InitStubs attempts to initialize the Tk stub table pointers and ensure that the correct version of Tk is loaded. In addition to an interpreter handle, it accepts as arguments a version number and a Boolean flag indicating whether the extension requires an exact version match or not. If exact is 0, then the extension is indicating that newer versions of Tk are acceptable as long as they have the same major version number as version; non-zero means that only the specified version is acceptable. Tcl_InitStubs returns a string containing the actual version of Tk satisfying the request, or NULL if the Tk version is not acceptable, does not support the stubs mechanism, or any other error condition occurred.

### SEE ALSO

Tcl_InitStubs

### KEYWORDS

stubs
Copyright © 1999 Scriptics Corporation