如何能修改已编译的exe文件使之调用当前目录下的dll？

bool runwithdll（char * pruncmd, char * pdllpath)
{
    char *    pcmd    = null;
    char *    pcurdir = null;
    bool    bpart    = false;
    char     szcurdir[1024];
    dword    dwlen;
    dword    i;
    while（*pruncmd == ' ')    pruncmd++;
    dwlen = （dword)strlen（pruncmd);
    for（i=0; i<dwlen; i++)
    {
        if（pruncmd[i] == ' ' && bpart == false)
        {
            pcmd = pruncmd + i;
            break;
        }
        if（pruncmd[i] == '"')
        {
            if（bpart)    bpart = false;
            else        bpart = true;
        }
    }
    if（pcmd == null)
    {
        pcmd = pruncmd;
    }
    for（; i>0; i--)
    {
        if（pruncmd[i] == '\\')
        {
            memset（szcurdir, 0, sizeof（szcurdir));
            if（pruncmd[0] == '"')
            {
                strncpy（szcurdir, pruncmd+1, i-1);
                szcurdir[i-1] = 0;
            }
            else
            {
                strncpy（szcurdir, pruncmd  , i  );
                szcurdir[i] = 0;
            }
            pcurdir = szcurdir;
            break;
        }
    }
//    msga（"pcmd:%s\r\npcurdir:%s", pcmd, pcurdir);
    process_information processinfo; 
    startupinfoa startupinfo;
    zeromemory（&startupinfo, sizeof（startupinfo));
    startupinfo.cb = sizeof（startupinfo);        //only compulsory field
    startupinfo.wshowwindow = sw_show;            //windows media player not show
    startupinfo.dwflags = startf_useshowwindow;        
    if（createprocessa（null, pruncmd, null, null, false, create_suspended, null,
        pcurdir, &startupinfo, &processinfo) == false)
    {
        return false;
    }
    if（procremtloaddll（processinfo.hprocess, pdllpath) == false)
    {
        ::resumethread（processinfo.hthread);
        closehandle（processinfo.hthread);
        closehandle（processinfo.hprocess);
        return false;
    }
    ::resumethread（processinfo.hthread);        //create_suspended  for wait the dll load done
    closehandle（processinfo.hthread);
    closehandle（processinfo.hprocess);
    return true;
}

hmodule procremtloaddll（handle hproc, char * pdllpath)
{
    byte    code[0x20];    //00
    hmodule hmodule;    //20
    int        nerror;        //24    //28 :pdllpath
    dword   dwsize = 0x20+4+4+1024, dwnedsize;
    char *    plibstr;
    bool    bret;
    fun1    pfunloadlib;
    handle    thd_hd;
    pfunloadlib = （fun1)::getprocaddress（::getmodulehandle（_t（"kernel32")), "loadlibrarya");
    if（pfunloadlib == null)
        return null;
    plibstr =（char *)virtualallocex（hproc, 0, dwsize, mem_commit, page_ＥＸＥＣute_readwrite);
    if（plibstr == null)
        return null;
    createthreadfun1（code, （dword)plibstr, （dword)pfunloadlib, （lpdword)（plibstr+0x20), （lpdword)（plibstr+0x24));
    dwnedsize = 0x20;
    bret = writeprocessmemory（hproc, plibstr, code, dwnedsize, &dwsize);            //复制代码
    if（bret == false || dwsize != dwnedsize )
    {
        virtualfreeex（hproc, plibstr, 0, mem_release );
        return null;
    }
    dwnedsize = （dword)strlen（pdllpath) + 1;
    bret = writeprocessmemory（hproc, plibstr+0x28, pdllpath, dwnedsize, &dwsize);    //复制参数
    if（bret == false || dwsize != dwnedsize )
    {
        virtualfreeex（hproc, plibstr, 0, mem_release );
        return null;
    }
    thd_hd = ::createremotethread（hproc, 0, 0, （lpthread_start_routine)plibstr, （void *)（plibstr+0x28), null, null);
    if（thd_hd == null)
    {
        virtualfreeex（hproc, plibstr, 0, mem_release);
        return null;
    }
    waitforsingleobject（thd_hd,infinite);
    closehandle（thd_hd);
    dwnedsize = 4;
    bret = ::readprocessmemory（hproc, plibstr+0x20, &hmodule, dwnedsize, &dwsize);
    if（bret == false || dwsize != dwnedsize )
    {
        virtualfreeex（hproc, plibstr, 0, mem_release);
        return null;
    }
    if（hmodule == null)
    {
        bret = ::readprocessmemory（hproc, plibstr+0x24, &nerror , dwnedsize, &dwsize);
        if（bret == false || dwsize != dwnedsize )
        {
            virtualfreeex（hproc, plibstr, 0, mem_release);
            return null;
        }
        ::setlasterror（nerror);
    }
    bret = virtualfreeex（hproc, plibstr, 0, mem_release);
    if（bret == false)
        return null;
    return hmodule;
}

lpbyte createthreadfun1（lpbyte pcode, dword dwcodeadr, dword dwcallfunadr, lpdword pfunretval, lpdword perror)
{
    dword    dwfunerror;
    dwfunerror = （dword)&getlasterror;
    *（dword *)（pcode + 0x00)    = 0x042474ff;            //push        d,[esp+04]
    *（ byte *)（pcode + 0x04)    = 0xe8;                    //call        *（dword *)（pcode + 0x05)    = dwcallfunadr - （4+5);    //            fun相对地址
    *（dword *)（pcode + 0x05)    = dwcallfunadr - （dwcodeadr+0x04+5);//            dwcallfunadr相对地址
    *（ byte *)（pcode + 0x09)    = 0xa3;                    //mov        [         ],eax
    *（dword *)（pcode + 0x0a)    = （dword)pfunretval;    //             funretval
    *（ byte *)（pcode + 0x0e)    = 0xe8;                    //call
    *（dword *)（pcode + 0x0f)    = dwfunerror -   （dwcodeadr+0x0e+5);//            getlasterror相对地址
    *（ byte *)（pcode + 0x13)    = 0xa3;                    //mov        [      ],eax
    *（dword *)（pcode + 0x14)    = （dword)perror;        //             perror
    *（ byte *)（pcode + 0x18)    = 0xc2;                    //retn
    *（ word *)（pcode + 0x19)    = 0x0004;                //            04  //一个参数返回
    *（ word *)（pcode + 0x1b)    = 0xcc;                    //int        3
    return pcode;
}