std map to vector for waitformultipleobjects parameter

cacoder · #1 14-Apr-2009, 12:26

Hi,

I have a set of channel objects. Each channel has a set of Win32 event objects associated with it. I want to store the Win32 event objects in a std::map as follows:

CPP / C++ / C Code:


std::map<unsigned int, std::vector<HANDLE>> channel_events;

for(unsigned int ch_index = 0; ch_index < 5; ch_index++)
{
  for(unsigned int event_index = 0; event_index < 4; event_index++)
  {
    channel_events[ch_index].push_back(CreateEvent(...));
    channel_events[ch_index].push_back(CreateEvent(...));
    channel_events[ch_index].push_back(CreateEvent(...));
  }
}

The problem is WaitForMultipleObjects(...) requires the event handles to be passed in as a const HANDLE *. So I can pass in a vector<HANDLE> as &events but I need to pass in the std::map above. Any ideas? I could always construct the std::map as an std::vector by sequentially ordering channel events into a long std::vector but not sure that's the best approach.

-cacoder

dlp · #2 14-Apr-2009, 19:54

If you're trying to wait for all the HANDLE objects in the map, you won't be able to do it this way. The alternative is to create an array of HANDLE and copy each handle into that as well as store it in your map. Question though, if both the event_index and the ch_index values go from 0 to some number continously, why not just use either a 2 dimensional array or 2 dimensional vector?

CPP / C++ / C Code:

std::vector< std::vector< HANDLE > > channel_events(5);
for(unsigned ch_index = 0; ch_index < 5; ch_index++)
{
  for(unsigned event_index = 0; event_index < 4; event_index++)
  {
    channel_events[ch_index].push_back(CreateEvent());
  }
}

cacoder · #3 15-Apr-2009, 18:25

You are correct in that I could just use a two dimensional vector. I decided to just use a one dimensional vector and have an enum index all events in the vector. It keeps the design simple.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Rate This Thread
Rate This Thread:

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Minimum value parameter problem	tones1986	C++ Forum	3	03-Apr-2006 10:46
find the value in the array that is closest in value to the second parameter	jack223	C++ Forum	4	04-Nov-2005 07:58
Help with syntax errors	PeteGallo	C Programming Language	7	08-Aug-2005 21:30
Re: Command Line Arguments, Part 1	WaltP	C Programming Language	0	11-Jul-2004 00:34
Re: Programming Techniques	WaltP	C Programming Language	0	10-Mar-2004 00:56

std map to vector for waitformultipleobjects parameter

Re: std map to vector for waitformultipleobjects parameter

Re: std map to vector for waitformultipleobjects parameter