I'm creating a custom build of node.js that should not show a console window to the user.
I've tried changing the linker config in the gyp file to 2 (which should set the linker flag /SUBSYSTEM:WINDOWS), but I still get a console window when I run the resulting node.exe binary.
How can I prevent the console window from appearing?
Edit: Further investigation reveals that the linker config in node.gyp is not taking effect. The generated node.vcxproj still has <Link><SubSystem>Console</SubSystem></Link> (which is very strange to me, since adding 'UACUIAccess': 'true' in the same part of node.gyp did take effect), so the built binary is incorrectly linked.
Solution 1
Save this one line of text as file invisible.vbs:
CreateObject(“Wscript.Shell”).Run “”"” & WScript.Arguments(0) & “”"”, 0, False
To run any program or batch file invisibly, use it like this:
wscript.exe “C:\Wherever\invisible.vbs” “C:\Some Other Place\MyBatchFile.bat”
To also be able to pass-on/relay a list of arguments use only two double quotes
CreateObject(“Wscript.Shell”).Run “” & WScript.Arguments(0) & “”, 0, False
eg: Invisible.vbs “Kill.vbs ME.exe”
Solution 2
Use a command line tool to silently launch a process : Quiet.
Solution 3
Roll your own C++ Win32 App:
PROCESS_INFORMATION procInfo = {0};
STARTUPINFOstartupInfo = {0};
SECURITY_ATTRIBUTESsaAttr = {0};
HANDLEhStdIn = GetStdHandle(STD_INPUT_HANDLE);
HANDLEhStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
HANDLEhStdErr = GetStdHandle(STD_ERROR_HANDLE);
// build up security attributes
saAttr.nLength = sizeof(saAttr);
saAttr.bInheritHandle = TRUE;
saAttr.lpSecurityDescriptor = NULL;
// set file handles for process to be created
startupInfo.cb = sizeof(startupInfo);
startupInfo.dwFlags = STARTF_USESTDHANDLES;
startupInfo.hStdInput = hStdIn;
startupInfo.hStdOutput = hStdOut;
startupInfo.hStdError = hStdErr;
// build command line: format is [cmd.exe /c "%batchScript%" %batchArgs%]
if (-1 == _snprintf_s(cmd, sizeof(cmd),"cmd.exe /c \"%s\" %s", batchScript, batchArgs))
errorExit("_snprintf_s(\"cmd.exe /c \"%%s\" %%s\"), \"%s\", \"%s\") failed.", batchScript, batchArgs);
rc = CreateProcess(NULL, cmd, NULL, &saAttr, TRUE, CREATE_NO_WINDOW, NULL, tempPath, &startupInfo, &procInfo);
You have to change the SubSystem field value in node.exe PE optional header. The current value is 3 which is defined as Windows Console. If you change it to 2 (which is defined as Windows GUI) there would be no console window. In order to patch the executable file, you have to use utilities to change Optional Header of PE.
One example of such a tool is PE tools.
Click on Optinal Header and then change the Subsystem from 3 to 2.
That`s all.
Remember that with this change you can only run js files. You can not use interactive mode.
It appears that you must:
Comment out the 'SubSystem': 1 line in common.gypi. (Changing it to 2 causes the build to fail in mksnapshot.)
Change SubSystem to 2 in node.gyp
Also add 'EntryPointSymbol': 'wmainCRTStartup' to node.gyp.
This builds a node.exe that does not create a console window.
Related
I have built a networking app for MacOS for private usage. It uses shell commands and runs bash files.
Most of my colleagues are using MacOS, but still need to publish the same app for Windows.
Is there any ways to hide a cmd window when I runs shell script?
Thanks in advance.
On Windows app, you can do that changing the folowing lines in windows/runner/resources/main.cpp
if (!::AttachConsole(ATTACH_PARENT_PROCESS) && ::IsDebuggerPresent()) {
CreateAndAttachConsole();
}
to this:
if (!::AttachConsole(ATTACH_PARENT_PROCESS) && ::IsDebuggerPresent()) {
CreateAndAttachConsole();
}else {
STARTUPINFO si = { 0 };
si.cb = sizeof(si);
si.dwFlags = STARTF_USESHOWWINDOW;
si.wShowWindow = SW_HIDE;
PROCESS_INFORMATION pi = { 0 };
WCHAR lpszCmd[MAX_PATH] = L"cmd.exe";
if (::CreateProcess(NULL, lpszCmd, NULL, NULL, FALSE, CREATE_NEW_CONSOLE | CREATE_NO_WINDOW, NULL, NULL, &si, &pi)) {
do {
if (::AttachConsole(pi.dwProcessId)) {
::TerminateProcess(pi.hProcess, 0);
break;
}
} while (ERROR_INVALID_HANDLE == GetLastError());
::CloseHandle(pi.hProcess);
::CloseHandle(pi.hThread);
}
}
More information here: https://github.com/flutter/flutter/issues/47891
There are some options to run a cmd hidden on Windows for example:
start a cmd window as hidden by using the "hide" option on a bat script or programmatically using the Windows API ShowWindow(SW_HIDE). Hidden in this case means you won't see the GUI and it has no presence on the task-bar.
run it through "Task Scheduler"
run it as background service
Some examples:
Bat script: How to run .BAT files invisibly without displaying the Command Prompt
C-sharp: Hide Command Window in Application
C-sharp: Run CMD command without displaying it
C-sharp: Sample code to schedule a task using WindowsTask Scheduler
I want to spawn a batch file from my FMX app (on Win32) with elevated privileges. From Remy's answer at the bottom of this thread on ShellExecute I found how to launch the batch file. Now, i can't figure out how to launch it with elevated privilege. Below is my code:
String Prog = "c:\\Users\\rwp\\Desktop\\test.bat";
int nErrorCode = (int) ShellExecute(NULL, L"runas", Prog.c_str(), NULL, NULL, SW_SHOWNORMAL);
if (nErrorCode <= 32) {
ShowMessage("an error occured");
}
I added "runas" for the second argument after reading this to no avail. Running the batch file manually (right-click and run as admin) works. Here is content of the batch file fyi (just kicks of a system imaging):
c:\Windows\system32\wbAdmin.exe start backup -backupTarget:D: -include:C: -allCritical -quiet
How can i ShellExecute this batch file as admin?
UPDATE 1: I'm attempting to use CreateProcess per Remy suggestion. Here is my code (based on this example):
//Code is inside a __fastcall button click
PROCESS_INFORMATION piProcInfo;
STARTUPINFO siStartInfo;
siStartInfo.cb = sizeof(STARTUPINFO);
siStartInfo.lpReserved = NULL;
siStartInfo.lpReserved2 = NULL;
siStartInfo.cbReserved2 = 0;
siStartInfo.lpDesktop = NULL;
siStartInfo.dwFlags = 0;
// String strCmdLine = "C:\\Users\\rwpatter\\Desktop\\test.bat";
String strCmdLine = "C:\\Windows\\System32\\wbAdmin.exe start backup -backupTarget:T: -include:C: -allCritical -quiet";
// Create the child process.
int rtrn = CreateProcess(
NULL,
strCmdLine.c_str(),
NULL, // process security attributes
NULL, // primary thread security attributes
0, // handles are inherited
0, // creation flags
0, // use parent's environment
0, // use parent's current directory
&siStartInfo, // STARTUPINFO pointer
&piProcInfo); // receives PROCESS_INFORMATION
// Wait for the processs to finish
DWORD rc = WaitForSingleObject(
piProcInfo.hProcess, // process handle
INFINITE);
ShowMessage(IntToStr(rtrn));
If I run it as shown (right-click on exe and run as admin) it returns 0 which means it failed. If I run it by putting the wbAdmin command line in the test.bat file (see commented line right above String strCmdLine in the code) then CreateProcess returns a 1 (success) but wbAdmin is still not running. It flashed a DOS window and i captured it as shown in the picture below. It shows oriental characters in the title bar and says not recognized as internal or external command. But, if i run that test.bat directly (elevated) it runs wbAdmin no problem.
Any ideas on what is wrong? Besides me obviously being ignorant. (p.s. i'll get to testing Golvind's answer on the ShellExecute after this...)
Running the batch file manually (right-click and run as admin) works.
Because you are running the 64-bit version of cmd when you start it manually.
It shows oriental characters in the title bar and says not recognized
as internal or external command.
Because your application is 32-bit. A 32-bit application does not see the same System32 folder as 64-bit applications. You can access the 64-bit System32 folder in 32-bit applications with the virtual sysnative folder.
#include <shellapi.h>
...
String strCmdLine = "wbAdmin.exe start backup -backupTarget:T: -include:C: -allCritical -quiet";
int rtrn = CreateProcess(
NULL,
strCmdLine.c_str(),
NULL, // process security attributes
NULL, // primary thread security attributes
0, // handles are inherited
0, // creation flags
0, // use parent's environment
0, // use parent's current directory
&siStartInfo, // STARTUPINFO pointer
&piProcInfo); // receives PROCESS_INFORMATION
if (!rtrn)
{
String newCmdLine = "c:\\windows\\sysnative\\wbAdmin.exe start backup -backupTarget:T: -include:C: -allCritical -quiet";
rtrn = CreateProcess(
NULL,
newCmdLine.c_str(),
NULL, // process security attributes
NULL, // primary thread security attributes
0, // handles are inherited
0, // creation flags
0, // use parent's environment
0, // use parent's current directory
&siStartInfo, // STARTUPINFO pointer
&piProcInfo); // receives PROCESS_INFORMATION
}
Or compile your application to 64-bit.
You need to launch CMD.exe as Administrator with "runas", and specify the batch file as a "run-me-then-exit" (i.e. /c) argument to command prompt, as so:
WCHAR wszCmdPath[MAX_PATH];
GetEnvironmentVariableW(L"ComSpec", wszCmdPath, MAX_PATH);
ShellExecuteW(NULL, L"runas", wszCmdPath, L"/c \"C:\\Path\\BatchFile.bat\"", L"", SW_SHOW);
Both functions called here can fail, and robust code would test for success before proceeding.
I need to start a process and have access to the PID, so I am trying to use ShellExecuteEx. I am attempting to open a batch file. However, no matter how I pass the parameters and no matter where the file is located and what permission's I have on the file, the function is returning with Error Code 5: Access is denied.
The File is located in the same location as the config files that have already been read successfully.
The File is set for full access permissions with any user.
It does this with any file type. I've tried just opening text files with the same outcome (Error 5)
If I use ShellExecute() instead, the batch file is run successfully.
Here is some of the code I've tried:
SHELLEXECUTEINFO exInfo;
exInfo.cbSize = sizeof(SHELLEXECUTEINFO);
exInfo.fMask = SEE_MASK_NOCLOSEPROCESS;
exInfo.lpVerb = "open";
exInfo.lpFile = "C:\\batchtest.bat";
exInfo.nShow = SW_NORMAL;
BOOL hReturnCode = ShellExecute(&exInfo);
DWORD LastError = GetLastError();
I've also tried:
SHELLEXECUTEINFO exInfo;
exInfo.cbSize = sizeof(SHELLEXECUTEINFO);
exInfo.fMask = SEE_MASK_NOCLOSEPROCESS;
exInfo.lpVerb = "open";
exInfo.lpFile = "C:\\Windows\\system32\\cmd.exe";
exInfo.lpParameters = "batchtest.bat";
And many variations of the above.
Also, I've tried something really simple like from here:
Get PID from ShellExecute
to no avail.
However this:
ShellExecute(NULL, "open", "C:\\testbat.bat", NULL, NULL, SW_SHOWNORMAL);
works without an error. Unfortunately, I need the PID, so I can't use ShellExecute.
Any suggestions would be greatly appreciated. I feel like I've exhausted all of my options.
Environment:
VS 2008
Windows 7
EDIT: fixed the code to "C:\batchtest.bat"; as suggested. (Still same result)
Figured it out.
In order to run batch file and I guess some other types of exe's on Windows 7, you have to elevate the call using the lpVerb = _TEXT("runas") -- even if you have UAC turned off. This isn't documented in the SHELLEXECUTEINFO structure documentation on MDSN (it isn't even given as an option), since it says: "The following verbs are commonly used"
The final code was as follows:
SHELLEXECUTEINFO exInfo;
exInfo.cbSize = sizeof(SHELLEXECUTEINFO);
exInfo.fMask = SEE_MASK_NOCLOSEPROCESS; //allows the PID to be returned
exInfo.hwnd = NULL;
exInfo.lpVerb = _TEXT("runas"); //elevates for Windows 7
exInfo.lpFile = "C:\\BatchTest.bat";
exInfo.lpParameters = NULL;
exInfo.nShow = SW_MAXIMIZE;
exInfo.hInstApp = NULL;
exInfo.lpDirectory = NULL;
BOOL hReturnCode = ShellExecuteEx(&exInfo);
I hope that helps others out.
Shouldn't the line
exInfo.lpFile = "C:\\batchtest.exe";
be
exInfo.lpFile = "C:\\batchtest.bat";
The code below for file with no-extension brings up a dialog shown below listing applications that can be used to open the file. This behavior is seen only from Windows-8. And the applications listed in the dialog are taken from HKEY_LOCAL_MACHINE\SOFTWARE\Classes*\OpenWithList. Is there anyway to suppress this dialog and get a behavior similar to old platforms?
-Karthik
SHELLEXECUTEINFO shinfo;
unsigned long mask = SEE_MASK_FLAG_NO_UI;
memset(&shinfo,0,sizeof(shinfo));
shinfo.cbSize = sizeof(shinfo);
shinfo.fMask = SEE_MASK_FLAG_DDEWAIT | mask;
shinfo.hwnd = NULL;
shinfo.lpVerb = "open";
shinfo.lpFile = prog;
shinfo.lpParameters = NULL;
shinfo.lpDirectory = 0;
shinfo.fMask = SEE_MASK_FLAG_NO_UI;
shinfo.nShow = SW_SHOWDEFAULT;
rc = ShellExecuteEx(&shinfo);
I'd suspect there is no default action associated with open on Windows 8 for files without an extension. I confirmed this using your code (a Delphi version of it, anyway) on Windows 7.
Running the code with shinfo.lpverb set to 'open' caused ShellExecuteEx to return FALSE, and GetLastError did indeed return ERROR_NO_ASSOCIATION. However, changing lpVerb to NULL (nil in Delphi) instead displayed the standard Win7 Open With dialog, just like your code does on Windows 8.
Here's a modified version of your code for testing:
SHELLEXECUTEINFO shinfo;
memset(&shinfo, 0, sizeof(shinfo));
shinfo.cbSize = sizeof(shinfo);
shinfo.fMask = SEE_MASK_FLAG_DDEWAIT | SEE_MASK_FLAG_NO_UI;
shinfo.lpVerb = NULL;
shinfo.lpFile = prog;
shinfo.hwnd = NULL;
shinfo.lpParameters = NULL;
shinfo.lpDirectory = 0;
shinfo.nShow = SW_SHOWDEFAULT;
rc = ShellExecuteEx(&shinfo);
Here's my test Delphi code for comparison (a quite literal translation of your C++ code):
var
shInfo: TShellExecuteInfo;
FillChar(shInfo, SizeOf(shInfo), 0); // Same result as memset()
shInfo.cbSize := SizeOf(shInfo);
shInfo.fMask := SEE_MASK_FLAG_NO_UI or SEE_MASK_FLAG_DDEWAIT;
shInfo.Wnd := 0;
shInfo.lpVerb := nil; // Also tested with 'open'
shInfo.lpDirectory := 'D:\TempFiles'; // Path to my no-extension file
shInfo.lpFile := 'datafile'; // My test file with no ext
shInfo.nShow := SW_SHOWDEFAULT;
if not ShellExecuteEx(#shInfo) then
ShowMessage(SysErrorMessage(GetLastError)); // Readable error message
A quick change to your code to replace "open" with NULL as the lpVerb should confirm.
You can also confirm my suspicion fairly easily by right-clicking a file with no extension in Win8's Explorer, and checking the bold default action at the top of the context menu. If there is no bold option, or if it's anything but open, my suspicions are correct.
I'm reading some code that uses fopen to open files for writing. The code needs to be able to close and rename these files from time to time (it's a rotating file logger). The author says that for this to happen the child processes must not inherit these FILE handles. (On Windows, that is; on Unix it's OK.) So the author writes a special subroutine that duplicates the handle as non-inheritable and closes the original handle:
if (!(log->file = fopen(log->path, mode)))
return ERROR;
#ifdef _WIN32
sf = _fileno(log->file);
sh = (HANDLE)_get_osfhandle(sf);
if (!DuplicateHandle(GetCurrentProcess(), sh, GetCurrentProcess(),
&th, 0, FALSE, DUPLICATE_SAME_ACCESS)) {
fclose(log->file);
return ERROR;
}
fclose(log->file);
flags = (*mode == 'a') ? _O_APPEND : 0;
tf = _open_osfhandle((intptr_t)th, _O_TEXT | flags);
if (!(log->file = _fdopen(tf, "at"))) {
_close(tf);
return ERROR;
}
#endif
Now, I'm also reading MSDN docs on fopen and see that their version of fopen has a Microsoft-specific flag that seems to do the same: the N flag:
N: Specifies that the file is not inherited by child processes.
Question: do I understand it correctly that I can get rid of that piece above and replace it (on Windows) with an additional N in the mode parameter?
Yes, you can.
fopen("myfile", "rbN") creates a non-inheritable file handle.
The N flag is not mentioned anywhere in Linux documentation for fopen, so the solution will be most probably not portable, but for MS VC it works fine.