Using standard printing from windows There are many applications where I don't really want to use the usual windows page print. Instead I want output to go directly to the printer using standard print i/o. It's actually a topic that is hard to find in any of the books on Windows, at least I've never found anything on it. But to my surprise I recently learned that standard (DOS/UNIX) printing is alive and well underneath windows. All we need to do is open a printer port and print to it. If the printer is directly attached to the computer it's trivial. The method for obtaining a printer port when the printer is on the network isn't hard either. The example below shows how I use the Windows NET USE command to re-direct LPT1 to a shared printer on an NT Server. The same technique applies for Novell networks with a slightly different syntax. Try this out by creating a new MFC Form-based project. Put a button on the form and attach this code to it. You can actually print with only 3 lines of code: FILE *fp = fopen("LPT1", "w"); fprintf(fp,"What's up, Doc?/n"); fclose(fp); Instant print gratification!! While the program is open it hogs the printer port. In my shop that isn't a problem but be aware of the effect on your windows spooled output. ********************************************************* THE CODE ********************************************************* // the headers for the conventional i/o routines #include #include #include using namespace std; // makes string and ofstream // work without std:: qualifier void CLineprtView::OnButton1() { // I could have used a CString instead of the buff[] // but I wanted to show how this is used with lightweight // ATL code and STD library char buff[MAX_BUFF_SIZE]; // My printer is located on another server so I must re-direct the // printer port. If the printer is directly attached this extra step // is not needed. // on my network the printer is published as //GREEN/hp5annex // All those back-slashes escape the backslash in the path name if (PRINTER_IS_REMOTE) { system("NET USE LPT1 /d"); // free up the port system("net use lpt1 ////green//hp5annex"); } // old fashioned file handle with // old fashioned open of the printer port FILE *ptr = fopen("LPT1","w"); // laser printer setup string sprintf(buff,"/033E/033(s0p4102t1b16.66H/033&l1O"); fprintf(ptr,buff); // old fashioned print fprintf(ptr,"Who of late doth make a thimble./n"); fprintf(ptr,"Is a lower bunk a status symbol??/n"); // old fashioned close fclose(ptr); // now the same thing with stream io ofstream optr("LPT1", ios::out); string str_text = "Hey Doc, Ain't this a print test from windows/n"; str_text += "with more lines to follow?/n"; optr << str_text << endl; optr << "Quiet, wabbit. I'm conversing with my muse!!/n"; optr << "That's all folks." << "/f" << flush; // add a formfeed // the printer connection is still open so close it optr.close(); // drop the network link if (PRINTER_IS_REMOTE) { system("net use lpt1 /d"); } } In practice I get printer path information from the registry on each machine, so the real live code is a little busier than this example, but not much. |
Using standard printing from windows
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