TCL tclOODecls.h Functions Not Exported - tcl

Question

My compiled TCL library (Tcl8.6.7, win7) didn't export the functions in tclOODecls.h. I exported the functions by putting: #define TCLAPI extern DLLEXPORT in tclOODecls.h before the auto generated section.
I would like to know why the functions were not exported by default and the preferred way of enabling the export.

Answer 1

The symbols have been defined to use MODULE_SCOPE. See issue 3010352 which mentions this a while ago. The idea is that if you want to use these symbols you should be using the Tcl stubs linking mechanism and define the USE_TCLOO_STUBS macro and link with the stubs library (tclstub86). The functions are in there - just not exported on the DLL exports.
From tcl.h:
/*
* Include platform specific public function declarations that are accessible
* via the stubs table. Make all TclOO symbols MODULE_SCOPE (which only
* has effect on building it as a shared library). See ticket [3010352].
*/
Example of static embedding Tcl with TclOO API usage
The following code will build an executable that works like the standard Tcl shell but includes an additional command that accesses the TclOO API as a demonstration.
/* Demonstrate embedding Tcl and using the TclOO API.
*
* Build with MSVC (adjust paths for local setup):
*
* cl -nologo -W3 -MT -Zi -GL -DSTATIC_BUILD -Ic:\opt\tcl\include test_embed_oo.c \
* -Fe:test_embed_oo.exe -link -debug -subsystem:console -ltcg -libpath:C:\src\tcl\kitgen\8.6\tcl\win\Release_VC13 \
* tcl86ts.lib user32.lib ws2_32.lib netapi32.lib
*
* Requires a static libary if Tcl (tcl86ts.lib on windows)
*/
#include <tcl.h>
#include <tclOO.h>
#include <locale.h>
static int
GetObjectNameCmd(ClientData clientData, Tcl_Interp *interp,
int objc, Tcl_Obj *const objv[])
{
int r = TCL_ERROR;
if (objc != 2) {
Tcl_WrongNumArgs(interp, 1, objv, "object");
return r;
}
Tcl_Object object = Tcl_GetObjectFromObj(interp, objv[1]);
if (object != NULL) {
Tcl_Obj *resultObj = Tcl_GetObjectName(interp, object);
if (resultObj != NULL) {
Tcl_SetObjResult(interp, resultObj);
r = TCL_OK;
}
}
return r;
}
#define TCL_LOCAL_APPINIT Custom_AppInit
int
Custom_AppInit(Tcl_Interp *interp)
{
Tcl_CreateObjCommand(interp, "getobjectname", GetObjectNameCmd, NULL, NULL);
return Tcl_Eval(interp, "source test_embed_oo.tcl");
}
#include "c:/src/tcl/kitgen/8.6/tcl/win/tclAppInit.c"
Embed Tcl using dynamic loading
Tcl can be linked to an application dynamically using the Tcl stubs linkage mechanism. This requires loading two functions from the DLL and then initializing the stubs table. The following shows this with TclOO access enabled.
/* Demonstrate embedding Tcl and using the TclOO API via stubs
*
* Build with MSVC (adjust paths for local setup):
*
* cl -nologo -W3 -MD -Zi -GL -Ic:\opt\tcl\include test_embed_oo_ex.c \
* -Fe:test_embed_oo_ex.exe -link -debug -ltcg -subsystem:console \
* -libpath:C:\opt\tcl\lib tclstub86.lib user32.lib
*
* Dynamically loads Tcl and then uses stubs for API access.
*/
#define WIN32_LEAN_AND_MEAN
#define STRICT
#include <windows.h>
#include <locale.h>
#define USE_TCL_STUBS
#define USE_TCLOO_STUBS
#include <tcl.h>
#include <tclOO.h>
static int
GetObjectNameCmd(ClientData clientData, Tcl_Interp *interp,
int objc, Tcl_Obj *const objv[])
{
int r = TCL_ERROR;
if (objc != 2) {
Tcl_WrongNumArgs(interp, 1, objv, "object");
return r;
}
Tcl_Object object = Tcl_GetObjectFromObj(interp, objv[1]);
if (object != NULL) {
Tcl_Obj *resultObj = Tcl_GetObjectName(interp, object);
if (resultObj != NULL) {
Tcl_SetObjResult(interp, resultObj);
r = TCL_OK;
}
}
return r;
}
typedef Tcl_Interp *(*LPFNTCLCREATEINTERP)();
typedef void *(*LPFNTCLFINDEXECUTABLE)(const char *);
static Tcl_Interp *
InitializeTcl(int argc, char *argv[])
{
Tcl_Interp *interp = NULL;
//Tcl_DString dString;
char szLibrary[16];
int nMinor;
HINSTANCE hTcl = NULL;
for (nMinor = 6; hTcl == NULL && nMinor > 4; nMinor--) {
wsprintfA(szLibrary, "tcl8%d.dll", nMinor);
hTcl = LoadLibraryA(szLibrary);
}
if (hTcl != NULL) {
LPFNTCLCREATEINTERP lpfnTcl_CreateInterp;
LPFNTCLFINDEXECUTABLE lpfnTcl_FindExecutable;
lpfnTcl_CreateInterp = (LPFNTCLCREATEINTERP)
GetProcAddress(hTcl, "Tcl_CreateInterp");
lpfnTcl_FindExecutable = (LPFNTCLFINDEXECUTABLE)
GetProcAddress(hTcl, "Tcl_FindExecutable");
if (lpfnTcl_CreateInterp != NULL) {
interp = lpfnTcl_CreateInterp();
if (interp != NULL) {
Tcl_InitStubs(interp, "8.6", 0);
#ifdef USE_TCLOO_STUBS
Tcl_OOInitStubs(interp);
#endif
lpfnTcl_FindExecutable(argv[0]);
Tcl_InitMemory(interp);
Tcl_Init(interp);
}
}
}
return interp;
}
/*
* Embed tcl interpreter into a C program.
*/
int
main(int argc, char *argv[])
{
Tcl_Interp *interp = NULL;
int r = TCL_ERROR;
setlocale(LC_ALL, "C");
interp = InitializeTcl(argc, argv);
if (interp == NULL) {
fprintf(stderr, "error: failed to initialize Tcl runtime\n");
} else {
Tcl_CreateObjCommand(interp, "getobjectname", GetObjectNameCmd, NULL, NULL);
if (argc > 1) {
r = Tcl_EvalFile(interp, argv[1]);
printf(Tcl_GetStringResult(interp));
}
Tcl_DeleteInterp(interp);
}
return r;
}
To test this you want a file that contains some tcl code that can call getobjectname and run the executable with the path to this file as the only argument.