Question

We have few printers connected in the network (LAN) setup with no domain controller. The printers are given specific IP addresses. I wish to log all the printer activities to a database (or file-system). Also I want to control the printers, for example, if any user (from a IP address) wishes to print in landscape but one my printers is configured only for printing in portrait, the printer should reject the print. Another example is that if a user has exceeded the print limit (number of pages), the printer should not print the next page.

I have no idea of achieving this. Kindly give your valuable suggestions. Code snippets, ideas are most welcome.

Answer 1

Please check out the Print Spooler API Functions over at MSDN: http://msdn.microsoft.com/en-us/library/dd162861(v=VS.85).aspx

How To Call Win32 Spooler Enumeration APIs Properly: http://support.microsoft.com/kb/158828

How to get the status of a printer and a print job: http://support.microsoft.com/kb/160129

Sample Code:

 BOOL GetJobs(HANDLE hPrinter,        /* Handle to the printer. */ 

                    JOB_INFO_2 **ppJobInfo, /* Pointer to be filled.  */ 
                    int *pcJobs,            /* Count of jobs filled.  */ 
                    DWORD *pStatus)         /* Print Queue status.    */ 

       {

       DWORD               cByteNeeded,
                            nReturned,
                            cByteUsed;
        JOB_INFO_2          *pJobStorage = NULL;
        PRINTER_INFO_2       *pPrinterInfo = NULL;

       /* Get the buffer size needed. */ 
           if (!GetPrinter(hPrinter, 2, NULL, 0, &cByteNeeded))
           {
               if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
                   return FALSE;
           }

           pPrinterInfo = (PRINTER_INFO_2 *)malloc(cByteNeeded);
           if (!(pPrinterInfo))
               /* Failure to allocate memory. */ 
               return FALSE;

           /* Get the printer information. */ 
           if (!GetPrinter(hPrinter,
                   2,
                   (LPSTR)pPrinterInfo,
                   cByteNeeded,
                   &cByteUsed))
           {
               /* Failure to access the printer. */ 
               free(pPrinterInfo);
               pPrinterInfo = NULL;
               return FALSE;
           }

           /* Get job storage space. */ 
           if (!EnumJobs(hPrinter,
                   0,
                   pPrinterInfo->cJobs,
                   2,
                   NULL,
                   0,
                   (LPDWORD)&cByteNeeded,
                   (LPDWORD)&nReturned))
           {
               if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
               {
                   free(pPrinterInfo);
                   pPrinterInfo = NULL;
                   return FALSE;
               }
           }

           pJobStorage = (JOB_INFO_2 *)malloc(cByteNeeded);
           if (!pJobStorage)
           {
               /* Failure to allocate Job storage space. */ 
               free(pPrinterInfo);
               pPrinterInfo = NULL;
               return FALSE;
           }

           ZeroMemory(pJobStorage, cByteNeeded);

           /* Get the list of jobs. */ 
           if (!EnumJobs(hPrinter,
                   0,
                   pPrinterInfo->cJobs,
                   2,
                   (LPBYTE)pJobStorage,
                   cByteNeeded,
                   (LPDWORD)&cByteUsed,
                   (LPDWORD)&nReturned))
           {
               free(pPrinterInfo);
               free(pJobStorage);
               pJobStorage = NULL;
               pPrinterInfo = NULL;
               return FALSE;
           }

           /*
            *  Return the information.
            */ 
           *pcJobs = nReturned;
           *pStatus = pPrinterInfo->Status;
           *ppJobInfo = pJobStorage;
           free(pPrinterInfo);

           return TRUE;

       }

       BOOL IsPrinterError(HANDLE hPrinter)
       {

           JOB_INFO_2  *pJobs;
           int         cJobs,
                       i;
           DWORD       dwPrinterStatus;

           /*
            *  Get the state information for the Printer Queue and
            *  the jobs in the Printer Queue.
            */ 
           if (!GetJobs(hPrinter, &pJobs, &cJobs, &dwPrinterStatus))
                return FALSE;

           /*
            *  If the Printer reports an error, believe it.
            */ 
           if (dwPrinterStatus &
               (PRINTER_STATUS_ERROR |
               PRINTER_STATUS_PAPER_JAM |
               PRINTER_STATUS_PAPER_OUT |
               PRINTER_STATUS_PAPER_PROBLEM |
               PRINTER_STATUS_OUTPUT_BIN_FULL |
               PRINTER_STATUS_NOT_AVAILABLE |
               PRINTER_STATUS_NO_TONER |
               PRINTER_STATUS_OUT_OF_MEMORY |
               PRINTER_STATUS_OFFLINE |
               PRINTER_STATUS_DOOR_OPEN))
           {
               free( pJobs );
               return TRUE;
           }

           /*
            *  Find the Job in the Queue that is printing.
            */ 
           for (i=0; i < cJobs; i++)
           {
               if (pJobs[i].Status & JOB_STATUS_PRINTING)
               {
                   /*
                    *  If the job is in an error state,
                    *  report an error for the printer.
                    *  Code could be inserted here to
                    *  attempt an interpretation of the
                    *  pStatus member as well.
                    */ 
                   if (pJobs[i].Status &
                       (JOB_STATUS_ERROR |
                       JOB_STATUS_OFFLINE |
                       JOB_STATUS_PAPEROUT |
                       JOB_STATUS_BLOCKED_DEVQ))
                   {
                       free( pJobs );
                       return TRUE;
                   }
               }
           }

           /*
            *  No error condition.
            */ 
           free( pJobs );
           return FALSE;

       }