I wrote a C program to use the tcl snack package. When I create a
Tcl_Interp in my program,I found that the Tcl_Interp includes only the
tcl package. When the program invoked the command "sound s -file
m1.wav", it failed with error msg"invalid command name 'sound' ".
Could someone tell me how to load the snack package in a Tcl_Interp?
Thanks in advance.

My program is attached as below.

#include<stdio.h>
#include<stdlib.h>
#include<tcl.h>

int main(int argc, _TCHAR* argv[])
{
        Tcl_Interp *pTclInterp = Tcl_CreateInterp();
        if(!pTclInterp)
        {
                printf("Tcl Interpreter could not be created.\n");
                return 0;
        }
        Tcl_Eval(pTclInterp," puts \"Hello ,world !\"");

        Tcl_Eval(pTclInterp, "package names");
        printf("%s\n", Tcl_GetString(Tcl_GetObjResult(pTclInterp)));

        Tcl_Eval(pTclInterp,"sound s -file m1.wav");
        printf("%s\n", Tcl_GetString(Tcl_GetObjResult(pTclInterp)));
        Tcl_Eval(pTclInterp,"s play -block 1");
        printf("%s\n", Tcl_GetString(Tcl_GetObjResult(pTclInterp)));
        Tcl_DeleteInterp(pTclInterp);
        return 0;

        if (Tcl_Init(pInterp) != TCL_OK) {
            printf("Tcl Interpreter could not be initialized.\n");
            return 0;
        }

Since Tcl has no built-in [sound] command, I suspect it is here
that you want to call Tcl_PkgRequire().