src/msw/utilsexc.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        msw/utilsexec.cpp
   3 // Purpose:     wxExecute implementation for MSW
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998-2002 wxWindows dev team
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation
  22 #endif
  23
  24 // For compilers that support precompilation, includes "wx.h".
  25 #include "wx/wxprec.h"
  26
  27 #ifdef __BORLANDC__
  28     #pragma hdrstop
  29 #endif
  30
  31 #ifndef WX_PRECOMP
  32     #include "wx/utils.h"
  33     #include "wx/app.h"
  34     #include "wx/intl.h"
  35 #endif
  36
  37 #include "wx/log.h"
  38
  39 #ifdef __WIN32__
  40     #include "wx/stream.h"
  41     #include "wx/process.h"
  42 #endif
  43
  44 #include "wx/msw/private.h"
  45
  46 #include <ctype.h>
  47
  48 #if !defined(__GNUWIN32__) && !defined(__WXWINE__) && !defined(__SALFORDC__) && !defined(__WXMICROWIN__)
  49     #include <direct.h>
  50 #ifndef __MWERKS__
  51     #include <dos.h>
  52 #endif
  53 #endif
  54
  55 #if defined(__GNUWIN32__) && !defined(__TWIN32__)
  56     #include <sys/unistd.h>
  57     #include <sys/stat.h>
  58 #endif
  59
  60 #if defined(__WIN32__) && !defined(__WXWINE__) && !defined(__WXMICROWIN__)
  61 #include <io.h>
  62
  63 #ifndef __GNUWIN32__
  64 #include <shellapi.h>
  65 #endif
  66 #endif
  67
  68 #include <stdio.h>
  69 #include <stdlib.h>
  70 #include <string.h>
  71 #ifndef __WATCOMC__
  72     #if !(defined(_MSC_VER) && (_MSC_VER > 800))
  73         #include <errno.h>
  74     #endif
  75 #endif
  76 #include <stdarg.h>
  77
  78 #if wxUSE_IPC
  79     #include "wx/dde.h"         // for WX_DDE hack in wxExecute
  80 #endif // wxUSE_IPC
  81
  82 // ----------------------------------------------------------------------------
  83 // constants
  84 // ----------------------------------------------------------------------------
  85
  86 // this message is sent when the process we're waiting for terminates
  87 #define wxWM_PROC_TERMINATED (WM_USER + 10000)
  88
  89 // ----------------------------------------------------------------------------
  90 // this module globals
  91 // ----------------------------------------------------------------------------
  92
  93 // we need to create a hidden window to receive the process termination
  94 // notifications and for this we need a (Win) class name for it which we will
  95 // register the first time it's needed
  96 static const wxChar *gs_classForHiddenWindow = NULL;
  97
  98 // ----------------------------------------------------------------------------
  99 // private types
 100 // ----------------------------------------------------------------------------
 101
 102 // structure describing the process we're being waiting for
 103 struct wxExecuteData
 104 {
 105 public:
 106     ~wxExecuteData()
 107     {
 108 #ifndef __WIN16__
 109         if ( !::CloseHandle(hProcess) )
 110         {
 111             wxLogLastError(wxT("CloseHandle(hProcess)"));
 112         }
 113 #endif
 114     }
 115
 116     HWND       hWnd;          // window to send wxWM_PROC_TERMINATED to
 117     HANDLE     hProcess;      // handle of the process
 118     DWORD      dwProcessId;   // pid of the process
 119     wxProcess *handler;
 120     DWORD      dwExitCode;    // the exit code of the process
 121     bool       state;         // set to FALSE when the process finishes
 122 };
 123
 124 #if defined(__WIN32__) && wxUSE_STREAMS
 125
 126 // ----------------------------------------------------------------------------
 127 // wxPipeStreams
 128 // ----------------------------------------------------------------------------
 129
 130 class wxPipeInputStream: public wxInputStream
 131 {
 132 public:
 133     wxPipeInputStream(HANDLE hInput);
 134     virtual ~wxPipeInputStream();
 135
 136     // returns TRUE if the pipe is still opened
 137     bool IsOpened() const { return m_hInput != INVALID_HANDLE_VALUE; }
 138
 139     // returns TRUE if there is any data to be read from the pipe
 140     bool IsAvailable() const;
 141
 142 protected:
 143     size_t OnSysRead(void *buffer, size_t len);
 144
 145 protected:
 146     HANDLE m_hInput;
 147 };
 148
 149 class wxPipeOutputStream: public wxOutputStream
 150 {
 151 public:
 152     wxPipeOutputStream(HANDLE hOutput);
 153     virtual ~wxPipeOutputStream();
 154
 155 protected:
 156     size_t OnSysWrite(const void *buffer, size_t len);
 157
 158 protected:
 159     HANDLE m_hOutput;
 160 };
 161
 162 // define this to let wxexec.cpp know that we know what we're doing
 163 #define _WX_USED_BY_WXEXECUTE_
 164 #include "../common/execcmn.cpp"
 165
 166 // ----------------------------------------------------------------------------
 167 // wxPipe represents a Win32 anonymous pipe
 168 // ----------------------------------------------------------------------------
 169
 170 class wxPipe
 171 {
 172 public:
 173     // the symbolic names for the pipe ends
 174     enum Direction
 175     {
 176         Read,
 177         Write
 178     };
 179
 180     // default ctor doesn't do anything
 181     wxPipe() { m_handles[Read] = m_handles[Write] = INVALID_HANDLE_VALUE; }
 182
 183     // create the pipe, return TRUE if ok, FALSE on error
 184     bool Create()
 185     {
 186         // default secutiry attributes
 187         SECURITY_ATTRIBUTES security;
 188
 189         security.nLength              = sizeof(security);
 190         security.lpSecurityDescriptor = NULL;
 191         security.bInheritHandle       = TRUE; // to pass it to the child
 192
 193         if ( !::CreatePipe(&m_handles[0], &m_handles[1], &security, 0) )
 194         {
 195             wxLogSysError(_("Failed to create an anonymous pipe"));
 196
 197             return FALSE;
 198         }
 199
 200         return TRUE;
 201     }
 202
 203     // return TRUE if we were created successfully
 204     bool IsOk() const { return m_handles[Read] != INVALID_HANDLE_VALUE; }
 205
 206     // return the descriptor for one of the pipe ends
 207     HANDLE operator[](Direction which) const
 208     {
 209         wxASSERT_MSG( which >= 0 && (size_t)which < WXSIZEOF(m_handles),
 210                       _T("invalid pipe index") );
 211
 212         return m_handles[which];
 213     }
 214
 215     // detach a descriptor, meaning that the pipe dtor won't close it, and
 216     // return it
 217     HANDLE Detach(Direction which)
 218     {
 219         wxASSERT_MSG( which >= 0 && (size_t)which < WXSIZEOF(m_handles),
 220                       _T("invalid pipe index") );
 221
 222         HANDLE handle = m_handles[which];
 223         m_handles[which] = INVALID_HANDLE_VALUE;
 224
 225         return handle;
 226     }
 227
 228     // close the pipe descriptors
 229     void Close()
 230     {
 231         for ( size_t n = 0; n < WXSIZEOF(m_handles); n++ )
 232         {
 233             if ( m_handles[n] != INVALID_HANDLE_VALUE )
 234             {
 235                 ::CloseHandle(m_handles[n]);
 236                 m_handles[n] = INVALID_HANDLE_VALUE;
 237             }
 238         }
 239     }
 240
 241     // dtor closes the pipe descriptors
 242     ~wxPipe() { Close(); }
 243
 244 private:
 245     HANDLE m_handles[2];
 246 };
 247
 248 #endif // wxUSE_STREAMS
 249
 250 // ============================================================================
 251 // implementation
 252 // ============================================================================
 253
 254 #ifdef __WIN32__
 255
 256 // ----------------------------------------------------------------------------
 257 // process termination detecting support
 258 // ----------------------------------------------------------------------------
 259
 260 // thread function for the thread monitoring the process termination
 261 static DWORD __stdcall wxExecuteThread(void *arg)
 262 {
 263     wxExecuteData *data = (wxExecuteData*)arg;
 264
 265     if ( ::WaitForSingleObject(data->hProcess, INFINITE) != WAIT_OBJECT_0 )
 266     {
 267         wxLogDebug(_T("Waiting for the process termination failed!"));
 268     }
 269
 270     // get the exit code
 271     if ( !::GetExitCodeProcess(data->hProcess, &data->dwExitCode) )
 272     {
 273         wxLogLastError(wxT("GetExitCodeProcess"));
 274     }
 275
 276     wxASSERT_MSG( data->dwExitCode != STILL_ACTIVE,
 277                   wxT("process should have terminated") );
 278
 279     // send a message indicating process termination to the window
 280     ::SendMessage(data->hWnd, wxWM_PROC_TERMINATED, 0, (LPARAM)data);
 281
 282     return 0;
 283 }
 284
 285 // window procedure of a hidden window which is created just to receive
 286 // the notification message when a process exits
 287 LRESULT APIENTRY _EXPORT wxExecuteWindowCbk(HWND hWnd, UINT message,
 288                                             WPARAM wParam, LPARAM lParam)
 289 {
 290     if ( message == wxWM_PROC_TERMINATED )
 291     {
 292         DestroyWindow(hWnd);    // we don't need it any more
 293
 294         wxExecuteData *data = (wxExecuteData *)lParam;
 295         if ( data->handler )
 296         {
 297             data->handler->OnTerminate((int)data->dwProcessId,
 298                                        (int)data->dwExitCode);
 299         }
 300
 301         if ( data->state )
 302         {
 303             // we're executing synchronously, tell the waiting thread
 304             // that the process finished
 305             data->state = 0;
 306         }
 307         else
 308         {
 309             // asynchronous execution - we should do the clean up
 310             delete data;
 311         }
 312
 313         return 0;
 314     }
 315     else
 316     {
 317         return DefWindowProc(hWnd, message, wParam, lParam);
 318     }
 319 }
 320
 321 // ============================================================================
 322 // implementation of IO redirection support classes
 323 // ============================================================================
 324
 325 #if wxUSE_STREAMS
 326
 327 // ----------------------------------------------------------------------------
 328 // wxPipeInputStreams
 329 // ----------------------------------------------------------------------------
 330
 331 wxPipeInputStream::wxPipeInputStream(HANDLE hInput)
 332 {
 333     m_hInput = hInput;
 334 }
 335
 336 wxPipeInputStream::~wxPipeInputStream()
 337 {
 338     if ( m_hInput != INVALID_HANDLE_VALUE )
 339         ::CloseHandle(m_hInput);
 340 }
 341
 342 bool wxPipeInputStream::IsAvailable() const
 343 {
 344     if ( !IsOpened() )
 345         return FALSE;
 346
 347     DWORD nAvailable;
 348
 349     // function name is misleading, it works with anon pipes as well
 350     DWORD rc = ::PeekNamedPipe
 351                     (
 352                       m_hInput,     // handle
 353                       NULL, 0,      // ptr to buffer and its size
 354                       NULL,         // [out] bytes read
 355                       &nAvailable,  // [out] bytes available
 356                       NULL          // [out] bytes left
 357                     );
 358
 359     if ( !rc )
 360     {
 361         if ( ::GetLastError() != ERROR_BROKEN_PIPE )
 362         {
 363             // unexpected error
 364             wxLogLastError(_T("PeekNamedPipe"));
 365         }
 366
 367         // don't try to continue reading from a pipe if an error occured or if
 368         // it had been closed
 369         ::CloseHandle(m_hInput);
 370
 371         wxConstCast(this, wxPipeInputStream)->m_hInput = INVALID_HANDLE_VALUE;
 372
 373         return FALSE;
 374     }
 375
 376     return nAvailable != 0;
 377 }
 378
 379 size_t wxPipeInputStream::OnSysRead(void *buffer, size_t len)
 380 {
 381     // reading from a pipe may block if there is no more data, always check for
 382     // EOF first
 383     if ( !IsAvailable() )
 384     {
 385         m_lasterror = wxSTREAM_EOF;
 386
 387         return 0;
 388     }
 389
 390     m_lasterror = wxSTREAM_NOERROR;
 391
 392     DWORD bytesRead;
 393     if ( !::ReadFile(m_hInput, buffer, len, &bytesRead, NULL) )
 394     {
 395         if ( ::GetLastError() == ERROR_BROKEN_PIPE )
 396             m_lasterror = wxSTREAM_EOF;
 397         else
 398             m_lasterror = wxSTREAM_READ_ERROR;
 399     }
 400
 401     return bytesRead;
 402 }
 403
 404 // ----------------------------------------------------------------------------
 405 // wxPipeOutputStream
 406 // ----------------------------------------------------------------------------
 407
 408 wxPipeOutputStream::wxPipeOutputStream(HANDLE hOutput)
 409 {
 410     m_hOutput = hOutput;
 411 }
 412
 413 wxPipeOutputStream::~wxPipeOutputStream()
 414 {
 415     ::CloseHandle(m_hOutput);
 416 }
 417
 418 size_t wxPipeOutputStream::OnSysWrite(const void *buffer, size_t len)
 419 {
 420     DWORD bytesRead;
 421
 422     m_lasterror = wxSTREAM_NOERROR;
 423     if ( !::WriteFile(m_hOutput, buffer, len, &bytesRead, NULL) )
 424     {
 425         if ( ::GetLastError() == ERROR_BROKEN_PIPE )
 426             m_lasterror = wxSTREAM_EOF;
 427         else
 428             m_lasterror = wxSTREAM_READ_ERROR;
 429     }
 430
 431     return bytesRead;
 432 }
 433
 434 #endif // wxUSE_STREAMS
 435
 436 #endif // Win32
 437
 438 // ============================================================================
 439 // wxExecute functions family
 440 // ============================================================================
 441
 442 #if wxUSE_IPC
 443
 444 // connect to the given server via DDE and ask it to execute the command
 445 static bool wxExecuteDDE(const wxString& ddeServer,
 446                          const wxString& ddeTopic,
 447                          const wxString& ddeCommand)
 448 {
 449     bool ok;
 450
 451     wxDDEClient client;
 452     wxConnectionBase *conn = client.MakeConnection(_T(""),
 453                                                    ddeServer,
 454                                                    ddeTopic);
 455     if ( !conn )
 456     {
 457         ok = FALSE;
 458     }
 459     else // connected to DDE server
 460     {
 461         // the added complication here is that although most
 462         // programs use XTYP_EXECUTE for their DDE API, some
 463         // important ones - like IE and other MS stuff - use
 464         // XTYP_REQUEST!
 465         //
 466         // so we try it first and then the other one if it
 467         // failed
 468         {
 469             wxLogNull noErrors;
 470             ok = conn->Request(ddeCommand) != NULL;
 471         }
 472
 473         if ( !ok )
 474         {
 475             // now try execute - but show the errors
 476             ok = conn->Execute(ddeCommand);
 477         }
 478     }
 479
 480     return ok;
 481 }
 482
 483 #endif // wxUSE_IPC
 484
 485 long wxExecute(const wxString& cmd, int flags, wxProcess *handler)
 486 {
 487     wxCHECK_MSG( !!cmd, 0, wxT("empty command in wxExecute") );
 488
 489     wxString command;
 490
 491 #if wxUSE_IPC
 492     // DDE hack: this is really not pretty, but we need to allow this for
 493     // transparent handling of DDE servers in wxMimeTypesManager. Usually it
 494     // returns the command which should be run to view/open/... a file of the
 495     // given type. Sometimes, however, this command just launches the server
 496     // and an additional DDE request must be made to really open the file. To
 497     // keep all this well hidden from the application, we allow a special form
 498     // of command: WX_DDE#<command>#DDE_SERVER#DDE_TOPIC#DDE_COMMAND in which
 499     // case we execute just <command> and process the rest below
 500     wxString ddeServer, ddeTopic, ddeCommand;
 501     static const size_t lenDdePrefix = 7;   // strlen("WX_DDE:")
 502     if ( cmd.Left(lenDdePrefix) == _T("WX_DDE#") )
 503     {
 504         // speed up the concatenations below
 505         ddeServer.reserve(256);
 506         ddeTopic.reserve(256);
 507         ddeCommand.reserve(256);
 508
 509         const wxChar *p = cmd.c_str() + 7;
 510         while ( *p && *p != _T('#') )
 511         {
 512             command += *p++;
 513         }
 514
 515         if ( *p )
 516         {
 517             // skip '#'
 518             p++;
 519         }
 520         else
 521         {
 522             wxFAIL_MSG(_T("invalid WX_DDE command in wxExecute"));
 523         }
 524
 525         while ( *p && *p != _T('#') )
 526         {
 527             ddeServer += *p++;
 528         }
 529
 530         if ( *p )
 531         {
 532             // skip '#'
 533             p++;
 534         }
 535         else
 536         {
 537             wxFAIL_MSG(_T("invalid WX_DDE command in wxExecute"));
 538         }
 539
 540         while ( *p && *p != _T('#') )
 541         {
 542             ddeTopic += *p++;
 543         }
 544
 545         if ( *p )
 546         {
 547             // skip '#'
 548             p++;
 549         }
 550         else
 551         {
 552             wxFAIL_MSG(_T("invalid WX_DDE command in wxExecute"));
 553         }
 554
 555         while ( *p )
 556         {
 557             ddeCommand += *p++;
 558         }
 559
 560         // if we want to just launch the program and not wait for its
 561         // termination, try to execute DDE command right now, it can succeed if
 562         // the process is already running - but as it fails if it's not
 563         // running, suppress any errors it might generate
 564         if ( !(flags & wxEXEC_SYNC) )
 565         {
 566             wxLogNull noErrors;
 567             if ( wxExecuteDDE(ddeServer, ddeTopic, ddeCommand) )
 568             {
 569                 // a dummy PID - this is a hack, of course, but it's well worth
 570                 // it as we don't open a new server each time we're called
 571                 // which would be quite bad
 572                 return -1;
 573             }
 574         }
 575     }
 576     else
 577 #endif // wxUSE_IPC
 578     {
 579         // no DDE
 580         command = cmd;
 581     }
 582
 583 #if defined(__WIN32__) && !defined(__TWIN32__)
 584
 585     // the IO redirection is only supported with wxUSE_STREAMS
 586     BOOL redirect = FALSE;
 587
 588 #if wxUSE_STREAMS
 589     wxPipe pipeIn, pipeOut, pipeErr;
 590
 591     // we'll save here the copy of pipeIn[Write]
 592     HANDLE hpipeStdinWrite = INVALID_HANDLE_VALUE;
 593
 594     // open the pipes to which child process IO will be redirected if needed
 595     if ( handler && handler->IsRedirected() )
 596     {
 597         // create pipes for redirecting stdin, stdout and stderr
 598         if ( !pipeIn.Create() || !pipeOut.Create() || !pipeErr.Create() )
 599         {
 600             wxLogSysError(_("Failed to redirect the child process IO"));
 601
 602             // indicate failure: we need to return different error code
 603             // depending on the sync flag
 604             return flags & wxEXEC_SYNC ? -1 : 0;
 605         }
 606
 607         redirect = TRUE;
 608     }
 609 #endif // wxUSE_STREAMS
 610
 611     // create the process
 612     STARTUPINFO si;
 613     wxZeroMemory(si);
 614     si.cb = sizeof(si);
 615
 616 #if wxUSE_STREAMS
 617     if ( redirect )
 618     {
 619         si.dwFlags = STARTF_USESTDHANDLES;
 620
 621         si.hStdInput = pipeIn[wxPipe::Read];
 622         si.hStdOutput = pipeOut[wxPipe::Write];
 623         si.hStdError = pipeErr[wxPipe::Write];
 624
 625         // when the std IO is redirected, we don't show the (console) process
 626         // window by default, but this can be overridden by the caller by
 627         // specifying wxEXEC_NOHIDE flag
 628         if ( !(flags & wxEXEC_NOHIDE) )
 629         {
 630             si.dwFlags |= STARTF_USESHOWWINDOW;
 631             si.wShowWindow = SW_HIDE;
 632         }
 633
 634         // we must duplicate the handle to the write side of stdin pipe to make
 635         // it non inheritable: indeed, we must close the writing end of pipeIn
 636         // before launching the child process as otherwise this handle will be
 637         // inherited by the child which will never close it and so the pipe
 638         // will never be closed and the child will be left stuck in ReadFile()
 639         HANDLE pipeInWrite = pipeIn.Detach(wxPipe::Write);
 640         if ( !::DuplicateHandle
 641                 (
 642                     ::GetCurrentProcess(),
 643                     pipeInWrite,
 644                     ::GetCurrentProcess(),
 645                     &hpipeStdinWrite,
 646                     0,                      // desired access: unused here
 647                     FALSE,                  // not inherited
 648                     DUPLICATE_SAME_ACCESS   // same access as for src handle
 649                 ) )
 650         {
 651             wxLogLastError(_T("DuplicateHandle"));
 652         }
 653
 654         ::CloseHandle(pipeInWrite);
 655     }
 656 #endif // wxUSE_STREAMS
 657
 658     PROCESS_INFORMATION pi;
 659     DWORD dwFlags = CREATE_DEFAULT_ERROR_MODE | CREATE_SUSPENDED;
 660
 661     bool ok = ::CreateProcess
 662                 (
 663                  NULL,              // application name (use only cmd line)
 664                  (wxChar *)
 665                  command.c_str(),   // full command line
 666                  NULL,              // security attributes: defaults for both
 667                  NULL,              //   the process and its main thread
 668                  redirect,          // inherit handles if we use pipes
 669                  dwFlags,           // process creation flags
 670                  NULL,              // environment (use the same)
 671                  NULL,              // current directory (use the same)
 672                  &si,               // startup info (unused here)
 673                  &pi                // process info
 674                 ) != 0;
 675
 676 #if wxUSE_STREAMS
 677     // we can close the pipe ends used by child anyhow
 678     if ( redirect )
 679     {
 680         ::CloseHandle(pipeIn.Detach(wxPipe::Read));
 681         ::CloseHandle(pipeOut.Detach(wxPipe::Write));
 682         ::CloseHandle(pipeErr.Detach(wxPipe::Write));
 683     }
 684 #endif // wxUSE_STREAMS
 685
 686     if ( !ok )
 687     {
 688 #if wxUSE_STREAMS
 689         // close the other handles too
 690         if ( redirect )
 691         {
 692             ::CloseHandle(pipeOut.Detach(wxPipe::Read));
 693             ::CloseHandle(pipeErr.Detach(wxPipe::Read));
 694         }
 695 #endif // wxUSE_STREAMS
 696
 697         wxLogSysError(_("Execution of command '%s' failed"), command.c_str());
 698
 699         return flags & wxEXEC_SYNC ? -1 : 0;
 700     }
 701
 702 #if wxUSE_STREAMS
 703     // the input buffer bufOut is connected to stdout, this is why it is
 704     // called bufOut and not bufIn
 705     wxStreamTempInputBuffer bufOut,
 706                             bufErr;
 707
 708     if ( redirect )
 709     {
 710         // We can now initialize the wxStreams
 711         wxPipeInputStream *
 712             outStream = new wxPipeInputStream(pipeOut.Detach(wxPipe::Read));
 713         wxPipeInputStream *
 714             errStream = new wxPipeInputStream(pipeErr.Detach(wxPipe::Read));
 715         wxPipeOutputStream *
 716             inStream = new wxPipeOutputStream(hpipeStdinWrite);
 717
 718         handler->SetPipeStreams(outStream, inStream, errStream);
 719
 720         bufOut.Init(outStream);
 721         bufErr.Init(errStream);
 722     }
 723 #endif // wxUSE_STREAMS
 724
 725     // register the class for the hidden window used for the notifications
 726     if ( !gs_classForHiddenWindow )
 727     {
 728         gs_classForHiddenWindow = _T("wxHiddenWindow");
 729
 730         WNDCLASS wndclass;
 731         wxZeroMemory(wndclass);
 732         wndclass.lpfnWndProc   = (WNDPROC)wxExecuteWindowCbk;
 733         wndclass.hInstance     = wxGetInstance();
 734         wndclass.lpszClassName = gs_classForHiddenWindow;
 735
 736         if ( !::RegisterClass(&wndclass) )
 737         {
 738             wxLogLastError(wxT("RegisterClass(hidden window)"));
 739         }
 740     }
 741
 742     // create a hidden window to receive notification about process
 743     // termination
 744     HWND hwnd = ::CreateWindow(gs_classForHiddenWindow, NULL,
 745                                WS_OVERLAPPEDWINDOW,
 746                                0, 0, 0, 0, NULL,
 747                                (HMENU)NULL, wxGetInstance(), 0);
 748     wxASSERT_MSG( hwnd, wxT("can't create a hidden window for wxExecute") );
 749
 750     // Alloc data
 751     wxExecuteData *data = new wxExecuteData;
 752     data->hProcess    = pi.hProcess;
 753     data->dwProcessId = pi.dwProcessId;
 754     data->hWnd        = hwnd;
 755     data->state       = (flags & wxEXEC_SYNC) != 0;
 756     if ( flags & wxEXEC_SYNC )
 757     {
 758         // handler may be !NULL for capturing program output, but we don't use
 759         // it wxExecuteData struct in this case
 760         data->handler = NULL;
 761     }
 762     else
 763     {
 764         // may be NULL or not
 765         data->handler = handler;
 766     }
 767
 768     DWORD tid;
 769     HANDLE hThread = ::CreateThread(NULL,
 770                                     0,
 771                                     wxExecuteThread,
 772                                     (void *)data,
 773                                     0,
 774                                     &tid);
 775
 776     // resume process we created now - whether the thread creation succeeded or
 777     // not
 778     if ( ::ResumeThread(pi.hThread) == (DWORD)-1 )
 779     {
 780         // ignore it - what can we do?
 781         wxLogLastError(wxT("ResumeThread in wxExecute"));
 782     }
 783
 784     // close unneeded handle
 785     if ( !::CloseHandle(pi.hThread) )
 786         wxLogLastError(wxT("CloseHandle(hThread)"));
 787
 788     if ( !hThread )
 789     {
 790         wxLogLastError(wxT("CreateThread in wxExecute"));
 791
 792         DestroyWindow(hwnd);
 793         delete data;
 794
 795         // the process still started up successfully...
 796         return pi.dwProcessId;
 797     }
 798
 799     ::CloseHandle(hThread);
 800
 801 #if wxUSE_IPC
 802     // second part of DDE hack: now establish the DDE conversation with the
 803     // just launched process
 804     if ( !ddeServer.empty() )
 805     {
 806         bool ok;
 807
 808         // give the process the time to init itself
 809         //
 810         // we use a very big timeout hoping that WaitForInputIdle() will return
 811         // much sooner, but not INFINITE just in case the process hangs
 812         // completely - like this we will regain control sooner or later
 813         switch ( ::WaitForInputIdle(pi.hProcess, 10000 /* 10 seconds */) )
 814         {
 815             default:
 816                 wxFAIL_MSG( _T("unexpected WaitForInputIdle() return code") );
 817                 // fall through
 818
 819             case -1:
 820                 wxLogLastError(_T("WaitForInputIdle() in wxExecute"));
 821
 822             case WAIT_TIMEOUT:
 823                 wxLogDebug(_T("Timeout too small in WaitForInputIdle"));
 824
 825                 ok = FALSE;
 826                 break;
 827
 828             case 0:
 829                 // ok, process ready to accept DDE requests
 830                 ok = wxExecuteDDE(ddeServer, ddeTopic, ddeCommand);
 831         }
 832     }
 833 #endif // wxUSE_IPC
 834
 835     if ( !(flags & wxEXEC_SYNC) )
 836     {
 837         // clean up will be done when the process terminates
 838
 839         // return the pid
 840         return pi.dwProcessId;
 841     }
 842
 843     // waiting until command executed (disable everything while doing it)
 844 #if wxUSE_GUI
 845     {
 846         wxBusyCursor bc;
 847
 848         wxWindowDisabler wd;
 849 #endif // wxUSE_GUI
 850
 851         // wait until the child process terminates
 852         while ( data->state )
 853         {
 854 #if wxUSE_STREAMS
 855             bufOut.Update();
 856             bufErr.Update();
 857 #endif // wxUSE_STREAMS
 858
 859             // don't eat 100% of the CPU -- ugly but anything else requires
 860             // real async IO which we don't have for the moment
 861             ::Sleep(50);
 862
 863             // repaint the GUI
 864             wxYield();
 865         }
 866
 867 #if wxUSE_GUI
 868     }
 869 #endif // wxUSE_GUI
 870
 871     DWORD dwExitCode = data->dwExitCode;
 872     delete data;
 873
 874     // return the exit code
 875     return dwExitCode;
 876 #else // Win16
 877     long instanceID = WinExec((LPCSTR) WXSTRINGCAST command, SW_SHOW);
 878     if (instanceID < 32)
 879         return flags & wxEXEC_SYNC ? -1 : 0;
 880
 881     if ( flags & wxEXEC_SYNC )
 882     {
 883         int running;
 884         do
 885         {
 886             wxYield();
 887             running = GetModuleUsage((HINSTANCE)instanceID);
 888         } while (running);
 889     }
 890
 891     return instanceID;
 892 #endif // Win16/32
 893 }
 894
 895 long wxExecute(char **argv, int flags, wxProcess *handler)
 896 {
 897     wxString command;
 898
 899     while ( *argv != NULL )
 900     {
 901         command << *argv++ << ' ';
 902     }
 903
 904     command.RemoveLast();
 905
 906     return wxExecute(command, flags, handler);
 907 }
 908