single_instance.h

实时监控

#ifndef _SINGLE_INSTANCE_H
#define _SINGLE_INSTANCE_H

class single_instance
{
	HANDLE x;
public:
	single_instance(LPCTSTR name): x(NULL)
	{
		x = CreateMutex(NULL, FALSE, name);
		if( GetLastError() == ERROR_ALREADY_EXISTS )
		{
			CloseHandle(x);
			x = NULL;
		}
	}
	~single_instance()
	{
		if( x )
		{
			CloseHandle(x);
			x = NULL;
		}
	}

	bool valid()
	{
		return x != NULL;
	}
};
#endif	// _SINGLE_INSTANCE_H