C / C++ / MFC

<br />
static UINT run(LPVOID p);<br />
void run();<br />
volatile BOOL running;<br />

<br />
void CMyView::doInvert()<br />
    {<br />
     running = TRUE;<br />
     AfxBeginThread(run, this);<br />
    }<br />
 <br />
UINT CMyView::run(LPVOID p)<br />
    {<br />
     CMyView * me = (CMyView *)p;<br />
     me->run();<br />
     return 0;<br />
    }<br />
 <br />
void CMyView::run()<br />
   {<br />
     for(int x=y = 0; running && y < image.height; y++)<br />
          for(int x = 0; running && x < image.width; x++)<br />
              changePixel(x, y);<br />
    running = FALSE;<br />
   }<br />

<br />
void CMyView::OnStop()<br />
   {<br />
    running = FALSE;<br />
   }

cv_k3n wrote:

Is is possible to close that program or stop it it while it is still in a 'for' loop?

kitty5 wrote:

1) So, I pass in the *buff. ReadFile() will dump the data there.
If I do another ReadFile() will it append to the end of *buff?
OR, will it overlap the data already in the *buff, if so,
how do I make subsequent writes into *buff append to the end of it?

kitty5 wrote:

2) Does ReadFile() automatically stick each 32-bit word out of the 1024 words it reads into each of the individual array slot of buff? So, that there will be a total of 256 array elements after the 1st call to ReadFile().

kitty5 wrote:

3) If "DWORD nNumberOfBytesToRead" is the min number of bytes to read, will
ReadFile() read more bytes if they are available? If so, how can you
limit ReadFile to only read the specified number of bytes?

Cedric Moonen wrote:

If you want to append it, you'll have to increment the address (something like buff+Offset). But warning !! As your buffer is a ULONG, it means that a single increment will point to the next ULONG (so 4 bytes further). It is not a good idea in this case to use a pointer to ULONG, use a pointer to UCHAR instead so you don't have to cast the pointer to a char area in order to be able to increment only one byte.

<br />
#define BUFF_SIZE = 0X400;<br />
ULONG numBytesRead = 0, offset = 0;<br />
UCHAR *buff = null;<br />
buff = new UCHAR[45000000];<br />
while(...)<br />
{<br />
   ReadFile(hndlPciAlt, buff, BUFF_SIZE, numBytesRead, NULL); //DMA data xfer<br />
}<br />

<br />
#define BUFF_SIZE = 0X400;<br />
ULONG numBytesRead = 0, offset = 0;<br />
UCHAR *buff = null;<br />
buff = new UCHAR[45000000];<br />
while(...)<br />
{<br />
   ReadFile(hndlPciAlt, (buff + offset), BUFF_SIZE, numBytesRead, NULL); //DMA data xfer<br />
   offset += numBytesRead;<br />
}<br />

kitty5 wrote:

Is (buff + offset) the proper syntax to increment the address of buff?

Steen Krogsgaard wrote:

ReadFile will wait until it has read these bytes (assuming you don't use overlapped I/O, but that's another story),

Steen Krogsgaard wrote:

Will ReadFile return true if there is a timeout?

kitty5 wrote:

buff = new ULONG[11250000]; //total of 11,250,000 32-bit words

konstantinos_1000 wrote:

control does not have the properties that in sample program displayed