🚀 go-pugleaf

Keith <kdopson@sbcglobal.net> wrote:
>
> [...] m_dcPrint = Prntr->Handle;

There is a known issue with TPrinter and it's Handle not being
valid. Try setting the TPrinter's Index prior to the call to
GetPrinter.

~ JD

JD wrote:

> Keith <kdopson@sbcglobal.net> wrote:
> >
> > [...] m_dcPrint = Prntr->Handle;
>
> There is a known issue with TPrinter and it's Handle not being
> valid. Try setting the TPrinter's Index prior to the call to
> GetPrinter.
>
> ~ JD

It matters not.  The source file for printers.pas shows the default
setting is for index is -1, the default printer, in the constructor:

constructor TPrinter.Create;
begin
  inherited Create;
  FPrinterIndex := -1;
end;

In fact prior to the original post, I had the ineffective line in the
source code, and I deleted that line Prntr->PrinterIndex=-1;
just prior to posting.

keith

Keith wrote:

>typedef struct
>{
>     WORD wSize;
>     BYTE bData[2];                  // placeholder
>} PASSTHROUGHSTRUCT, FAR *LPPTS;
>
>LPPTS m_lpPTS;

Don't rely on "magic".
You rely on m_lpPTS being NULL, so set it.
	LPPTS  m_lpPTS = NULL;

>if (!m_lpPTS)
>  {
>  m_lpPTS = (LPPTS)GlobalLock(GlobalAlloc(GPTR, sizeof(WORD) +
>                                     2048));

Incorrect.
GPTR includes GMEM_FIXED, which is already locked, AND it returns the
Address, not a Handle. Also not sure why you want is Zero Initialized.

	m_lpPTS = (LPPTS)GlobalAlloc(GMEM_FIXED, 2050 );

>char *PrintThis="Now is the time for all good men to come to the aid of
>his country and Liz need not be offended.\r\n"
>m_lpPTS->wSize = strlen(PrintThis);
>
>memcpy (m_lpPTS->bData, PrintThis, strlen(PrintThis));
>
>int rv=1;
>for (int i=0;rv && i<30;++i)
>  {
>  rv=Escape(m_dcPrint,PASSTHROUGH,sizeof(m_lpPTS->wSize) +
>m_lpPTS->wSize,
>         (LPSTR)m_lpPTS,0);
>  }

You don't check for failure of the Escape.
You only check if it is implimented (zero return).
Are you sure the printer wants to see the size field?
I would think this would be more appropriate...

static  char  PrintThis[] = "Now is the time for all good men to come
to the aid of his country and Liz need not be offended.\r\n";

  rv=Escape( m_dcPrint ,PASSTHROUGH, sizeof(PrintThis)-1, PrintThis);
  if( rv <= 0 )
  {
	/* handle error */
	break;
   };

>EndPage(m_dcPrint);
>EndDoc(m_dcPrint);
>GlobalUnlock(m_lpPTS);

You forgot GlobalFree()
Also, since your Lock was incorrect, the Unlock is too...

	EndPage(m_dcPrint);
	EndDoc(m_dcPrint);
	GlobalFree(m_lpPTS);
	m_lpPTS = NULL;

I also didn't see where you actually Opened the Printer, or Closed it.

> Any of you folks have an explanation why there is no printed output?
> or, alternatively, any of you ever use the Escape to attempt to send
> data, for instance, PCL-5 commands, to a HP laser printer?
>
> TIA
>
> keith

For the schlep (er, hacker, i.e. programmer) who tries the above, look at
this MSDN URL:
http://support.microsoft.com/kb/138594/EN-US/

Use esc-E with caution in your raw transmissions to the printer if you use
downloaded fonts or printer macros.  Same with form feed cautions... the
spooler may also send form feeds on page breaks (...may).. and your specific
printer may, or may not, eject pages, depending on whether its raster
actually contains printable data.  Also note the value of DocInfo.pDatatype
being set to 'RAW', which doesn't appear to be defined as such in BCB.

Your best bet is 'probably' to use the printer's port as a file
open/write/close.  Unfortunately, you do not get the notifications of
document print status that winspool provides through callback.

keith