stefankueng / sendmessage

SendMessage is a little tool to send Windows messages to any window.

SendMessage

SendMessage is a little tool to send Windows messages to any window.

Ever wondered how you should test whether your application correctly responds to certain system messages like WM_ENDSESSION or WM_POWERBROADCAST? Of course you can test your application by actually triggering those messages, but especially the WM_ENDSESSION message and its purpose makes it impossible to attach a debugger to your application once Windows sends you that message.

With this tool, you can send that message and any other message you like to your application window. And you can do that while you have a debugger attached to your application!

Please visit the homepage of SendMessage for more information.

sendmessage's Issues

Crash when dragging target across text editor windows

The accessible name of a text editor window is its contents, which overflows the buffer in DisplayInfoOnFoundWindow. This can be easily fixed as shown in this extract, where lines containing szAccName are changed or new:

`bool CMainDlg::DisplayInfoOnFoundWindow(HWND hwndFoundWindow)
{
RECT rect; // Rectangle area of the found window.
TCHAR szText[512];
TCHAR szClassName[100];
TCHAR szAccName[100];

// Get the screen coordinates of the rectangle of the found window.
GetWindowRect(hwndFoundWindow, &rect);

// Get the class name of the found window.
GetClassName(hwndFoundWindow, szClassName, _countof(szClassName));

// Get its accessible name.
_tcsncpy_s(szAccName, _countof(szAccName), CAccessibleName(hwndFoundWindow).c_str(), _TRUNCATE);

// Display some information on the found window.
_stprintf_s
    (
    szText, _countof(szText), _T("Window Handle == 0x%p\r\nClass Name : %s\r\nAccessible Name : %s\r\nRECT == { Left: %d, Top: %d, Right: %d, Bottom: %d }\r\n"),
    hwndFoundWindow,
    szClassName,
    szAccName,
    rect.left,
    rect.top,
    rect.right,
    rect.bottom
    );

`

Use CLang + MinGW-w64 for build

VisualStudio is a non-free toolchain.

Use _set_invalid_parameter_handler so app doesn't crash when ie: buffer overflows

Hi, thanks for the tool, very useful.

Your tool crashed for me while trying to diagnose an application, caused by the accessible name (Scintilla is the underlying Hwnd, doing something strange) being longer than approx 512 chars (in DisplayInfoOnFoundWindow). By default, the invalid parameter handler for the safe CRT functions crash the application.

It would probably better to allow the app to continue running, with a truncated name. The handler can be changed by setting the _set_invalid_parameter_handler.

I can submit a pull request if you are ok with this.

WM_COPYDATA消息没啥反应，有没有测试过？

发送WM_COPYDATA没反应，那几个参数应该怎么设？

WM_SETTEXT Can't Send string

I can't send a WM_SETTEXT message to Notepad to set the text, it just clears what was written.

Use CMake for build

It provides suppkrt of multiple toolchains.

Cant send keys to admin terminal?

I've been using this alongside task scheduler to write to cmd on a schedule (using a bat script). Had to run the process under the administrators group to use another command, which broke sendmessage as commands are no longer sent to the existing terminal. Is there any way to force sendmessage to an administrator terminal?

Example snippet from bat file:

SendMessage64.exe /windowtitle: "Test Window" /message:WM_CHAR /wparam:116 /1param:1

Not possibe to send WM_COPYDATA?

It looks like the lParam has to be a pointer to a struct?

(otherwise very helpfull tool)

[Help] How to send CTRL+C (graceful shutdown) to a opened .jar on CMD

I can't figure out how to send a "CTRL+C" to the open java window to tell it to do a graceful shutdown (a batch running this .jar in a CMD with a specific window title).
The problem is that the only command I find, closes the window instant.
In theory the value "0x03" should see it as "CTRL+C" but I don't know where to write it.

Thanks in advance