Dear Friends,
Is there any way by which I can check whether a printer is offline or online
Regards
Anser
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;
}
function IsPrint( QuePrinter )
LOCAL nStatus
DEFAULT QuePrinter := "LPT1:"
nStatus := PrnStatus( QuePrinter )
if nStatus < 1 ; return "Impressora OK"
elseif nStatus = 1 ; return "Impressora Pausada"
elseif nStatus = 2 ; return "Impressora com Erro"
elseif nStatus = 4 ; return "Impressora Deletando"
elseif nStatus = 8 ; return "Impressora em Modo Bandeja"
elseif nStatus = 16 ; return "Impressora Sem Papel"
elseif nStatus = 32 ; return "Impressora em Modo Manual"
elseif nStatus = 64 ; return "Impressora com Problema no Papel"
elseif nStatus = 128 ; return "Impressora OffLine"
elseif nStatus = 256 ; return "Impressora com IO Ativo"
elseif nStatus = 512 ; return "Impressora Ocupada"
elseif nStatus = 1024 ; return "Impressora Imprimindo"
elseif nStatus = 2048 ; return "Impressora Memoria Lotada"
elseif nStatus = 4096 ; return "Impressora Nao Instalada"
elseif nStatus = 8192 ; return "Impressora Aguardando"
elseif nStatus = 16384 ; return "Impressora Processando"
elseif nStatus = 32768 ; return "Impressora Inicializando"
elseif nStatus = 65536 ; return "Impressora em Atencao"
elseif nStatus = 131072 ; return "Impressora Toner Baixo"
elseif nStatus = 262144 ; return "Impressora Sem Toner"
elseif nStatus = 524288 ; return "Impressora PAGE_PUNT"
elseif nStatus = 1048576 ; return "Impressora Intervencao do Usuario"
elseif nStatus = 2097152 ; return "Impressora Sem Memoria"
elseif nStatus = 4194304 ; return "Impressora Tampa Aberta"
elseif nStatus = 8388608 ; return "Impressora Servidor Desconhecido"
elseif nStatus = 16777217 ; return "Impressora POWER_SAVE"
endif
return nil
nStatus := PrnStatus( QuePrinter )
if nStatus < 1 ; return "Printer OK" // ie Impressora OK
elseif nStatus = 128 ; return "Printer OFFLINE"
*------------------------------------------*
Function TestPrn()
*------------------------------------------*
Local nPrn,cFileName:="D:\WinAcs\MyText.Txt"
MsgInfo(isprint(PrnGetName()) )
nPrn := PrintFileRaw(PrnGetName(),cFileName, "Test for PrintFileRaw()")
MsgInfo("Entered TestPrn, value of nPrn is "+str(nPrn))
IF nPrn < 0
DO CASE
CASE nPrn = -1
Alert(cMess+"Incorrect parameters passed to function")
CASE nPrn = -2
Alert(cMess+"WINAPI OpenPrinter() call failed")
CASE nPrn = -3
Alert(cMess+"WINAPI StartDocPrinter() call failed")
CASE nPrn = -4
Alert(cMess+"WINAPI StartPagePrinter() call failed")
CASE nPrn = -5
Alert(cMess+"WINAPI malloc() of memory failed")
CASE nPrn = -6
Alert(cMess+"WINAPI CreateFile() failed - File "+cFileName+" not found??")
OTHERWISE
Alert(cFileName+" PRINTED OK!!!?")
ENDCASE
ENDIF
// The next few lines automate protection from a GPF if printer not available...
hDC := GetPrintDefault( GetActiveWindow() )
SysRefresh()
IF hDC = 0 // Handle rare case where computer has no printer.
cParam := "X" // (Previously, this param had to be manually entered when
ENDIF // launching the app.)
IF EMPTY(cParam) .OR. cParam # "X"
// The following may cause a crash if the workstation's
// default network printer is unavailable...
cOldPrinter := PrnGetName()
ELSE // cParam = "X"...
MsgInfo("To correct a problem with default printer, on the "+CRLF+;
"next dialog box, select the printer you want to use.","Fix printer selection...")
PrinterSetup()
SysRefresh()
cOldPrinter := PrnGetName()
ENDIF
function IsPrint( QuePrinter )
LOCAL nStatus
DEFAULT QuePrinter := "LPT1:"
nStatus := PrnStatus( QuePrinter )
if nStatus < 1 ; return "Impressora OK" // "Printer OK"
elseif nStatus = 1 ; return "Impressora Pausada" // "Printer Paused"
elseif nStatus = 2 ; return "Impressora com Erro" // "Printer Error"
elseif nStatus = 4 ; return "Impressora Deletando" // "Printer Deleting"
elseif nStatus = 8 ; return "Impressora em Modo Bandeja" // "Printer Tray Mode"
elseif nStatus = 16 ; return "Impressora Sem Papel" // "Printer Without Paper"
elseif nStatus = 32 ; return "Impressora em Modo Manual" // "Printer In Manual Way"
elseif nStatus = 64 ; return "Impressora com Problema no Papel" // "Printer Paper Problem"
elseif nStatus = 128 ; return "Impressora OffLine" // "Printer OffLine"
elseif nStatus = 256 ; return "Impressora com IO Ativo" // "Printer With Active IO"
elseif nStatus = 512 ; return "Impressora Ocupada" // "Printer Occupied"
elseif nStatus = 1024 ; return "Impressora Imprimindo" // "Printer Printing"
elseif nStatus = 2048 ; return "Impressora Memoria Lotada" // "Printer Memory Full"
elseif nStatus = 4096 ; return "Impressora Nao Instalada" // "Printer Not Installed"
elseif nStatus = 8192 ; return "Impressora Aguardando" // "Printer Waiting"
elseif nStatus = 16384 ; return "Impressora Processando" // "Printer Processing"
elseif nStatus = 32768 ; return "Impressora Inicializando" // "Printer Initializing"
elseif nStatus = 65536 ; return "Impressora em Atencao" // "Printer ???"
elseif nStatus = 131072 ; return "Impressora Toner Baixo" // "Printer Toner Low"
elseif nStatus = 262144 ; return "Impressora Sem Toner" // "Printer Without Toner"
elseif nStatus = 524288 ; return "Impressora PAGE_PUNT" // "Printer Page Eject"
elseif nStatus = 1048576 ; return "Impressora Intervencao do Usuario" // "Printer User Intervention"
elseif nStatus = 2097152 ; return "Impressora Sem Memoria" // "Printer Without Memory"
elseif nStatus = 4194304 ; return "Impressora Tampa Aberta" // "Printer Open Cover"
elseif nStatus = 8388608 ; return "Impressora Servidor Desconhecido" // "Printer Server Disconnected"
elseif nStatus = 16777217 ; return "Impressora POWER_SAVE" // "Printer Power Saver"
endif
function IsPrint( QuePrinter, cLang )
LOCAL aMsg := {},nStatus
DEFAULT QuePrinter := "LPT1:"
DEFAULT cLang := "E" // "P" = Portuguese; "E" = English
nStatus := PrnStatus( QuePrinter )
if cLang == "P" // Portuguese nStatus value...
AADD(aMsg, "Impressora OK") // < 1
AADD(aMsg, "Impressora Pausada") // = 1
AADD(aMsg, "Impressora com Erro") // = 2
AADD(aMsg, "Impressora Deletando") // = 4
AADD(aMsg, "Impressora em Modo Bandeja") // = 8
AADD(aMsg, "Impressora Sem Papel") // = 16
AADD(aMsg, "Impressora em Modo Manual") // = 32
AADD(aMsg, "Impressora com Problema no Papel") // = 64
AADD(aMsg, "Impressora OffLine") // = 128
AADD(aMsg, "Impressora com IO Ativo") // = 256
AADD(aMsg, "Impressora Ocupada") // = 512
AADD(aMsg, "Impressora Imprimindo") // = 1024
AADD(aMsg, "Impressora Memoria Lotada") // = 2048
AADD(aMsg, "Impressora Nao Instalada") // = 4096
AADD(aMsg, "Impressora Aguardando") // = 8192
AADD(aMsg, "Impressora Processando") // = 16384
AADD(aMsg, "Impressora Inicializando") // = 32768
AADD(aMsg, "Impressora em Atencao") // = 65536
AADD(aMsg, "Impressora Toner Baixo") // = 131072
AADD(aMsg, "Impressora Sem Toner") // = 262144
AADD(aMsg, "Impressora PAGE_PUNT") // = 524288
AADD(aMsg, "Impressora Intervencao do Usuario") // = 1048576
AADD(aMsg, "Impressora Sem Memoria") // = 2097152
AADD(aMsg, "Impressora Tampa Aberta") // = 4194304
AADD(aMsg, "Impressora Servidor Desconhecido") // = 8388608
AADD(aMsg, "Impressora POWER_SAVE") // = 16777217
else
AADD(aMsg, "Printer OK") // < 1
AADD(aMsg, "Printer Paused") // = 1
AADD(aMsg, "Printer Error") // = 2
AADD(aMsg, "Printer Deletion Pending") // = 4
AADD(aMsg, "Printer Paper Jam") // = 8
AADD(aMsg, "Printer Without Paper") // = 16
AADD(aMsg, "Printer Manual Feed") // = 32
AADD(aMsg, "Printer Paper Problem") // = 64
AADD(aMsg, "Printer OffLine") // = 128
AADD(aMsg, "Printer IO Active") // = 256
AADD(aMsg, "Printer Busy") // = 512
AADD(aMsg, "Printer Printing") // = 1024
AADD(aMsg, "Printer Output Bin Full") // = 2048
AADD(aMsg, "Printer Not Available") // = 4096
AADD(aMsg, "Printer Waiting") // = 8192
AADD(aMsg, "Printer Processing") // = 16384
AADD(aMsg, "Printer Initializing") // = 32768
AADD(aMsg, "Printer Warming Up") // = 65536
AADD(aMsg, "Printer Toner Low") // = 131072
AADD(aMsg, "Printer Without Toner") // = 262144
AADD(aMsg, "Printer Page Punt") // = 524288
AADD(aMsg, "Printer User Intervention") // = 1048576
AADD(aMsg, "Printer Out Of Memory") // = 2097152
AADD(aMsg, "Printer Door Open") // = 4194304
AADD(aMsg, "Printer Server Unknown") // = 8388608
AADD(aMsg, "Printer Power Save") // = 16777217
endif
if nStatus < 1 ; return aMsg[1] // "Printer OK"
elseif nStatus = 1 ; return aMsg[2] // "Printer Paused"
elseif nStatus = 2 ; return aMsg[3] // "Printer Error"
elseif nStatus = 4 ; return aMsg[4] // "Printer Deletion Pending"
elseif nStatus = 8 ; return aMsg[5] // "Printer Paper Jam"
elseif nStatus = 16 ; return aMsg[6] // "Printer Without Paper"
elseif nStatus = 32 ; return aMsg[7] // "Printer Manual Feed"
elseif nStatus = 64 ; return aMsg[8] // "Printer Paper Problem"
elseif nStatus = 128 ; return aMsg[9] // "Printer OffLine"
elseif nStatus = 256 ; return aMsg[10] // "Printer IO Active"
elseif nStatus = 512 ; return aMsg[11] // "Printer Busy"
elseif nStatus = 1024 ; return aMsg[12] // "Printer Printing"
elseif nStatus = 2048 ; return aMsg[13] // "Printer Output Bin Full"
elseif nStatus = 4096 ; return aMsg[14] // "Printer Not Available"
elseif nStatus = 8192 ; return aMsg[15] // "Printer Waiting"
elseif nStatus = 16384 ; return aMsg[16] // "Printer Processing"
elseif nStatus = 32768 ; return aMsg[17] // "Printer Initializing"
elseif nStatus = 65536 ; return aMsg[18] // "Printer Warming Up"
elseif nStatus = 131072 ; return aMsg[19] // "Printer Toner Low"
elseif nStatus = 262144 ; return aMsg[20] // "Printer Without Toner"
elseif nStatus = 524288 ; return aMsg[21] // "Printer Page Punt"
elseif nStatus = 1048576 ; return aMsg[22] // "Printer User Intervention"
elseif nStatus = 2097152 ; return aMsg[23] // "Printer Out Of Memory"
elseif nStatus = 4194304 ; return aMsg[24] // "Printer Door Open"
elseif nStatus = 8388608 ; return aMsg[25] // "Printer Server Unknown"
elseif nStatus = 16777217 ; return aMsg[26] // "Printer Power Save"
endif
1. What the Printer object missed
Printing has long been a very problematic part of developing complete and professional applications in Visual Basic. This was redressed to a large degree with the new Printer object introduced in Visual Basic 4.
However, there are shortcomings with this object. The biggest shortcoming is that you cannot find out whether the printer is ready, busy, out of paper etc. from your application.
However, there is an API call, GetPrinter which returns a great deal more information about a printer.
<-- API Declaration -->
Private Declare Function GetPrinterApi Lib "winspool.drv" Alias _
"GetPrinterA" (ByVal hPrinter As Long, _
ByVal Level As Long, _
buffer As Long, _
ByVal pbSize As Long, _
pbSizeNeeded As Long) As Long
This takes the handle to a printer in hPrinter and fills the buffer provided to it with information from the printer driver. To get the handle from the Printer object, you need to use the OpenPrinter API call.
This handle must be released using the ClosePrinter API call as soon as you are finished with it.
<-- API Declaration -->
Private Type PRINTER_DEFAULTS
pDatatype As String
pDevMode As DEVMODE
DesiredAccess As Long
End Type
Private Declare Function OpenPrinter Lib "winspool.drv" _
Alias "OpenPrinterA" (ByVal pPrinterName As String, _
phPrinter As Long, pDefault As PRINTER_DEFAULTS) As Long
Private Declare Function ClosePrinter Lib "winspool.drv" _
(ByVal hPrinter As Long) As Long
You pass the Printer.DeviceName to this to get the handle.
<-- Use -->
Dim lret As Long
Dim pDef As PRINTER_DEFAULTS
lret = OpenPrinter(Printer.DeviceName, mhPrinter, pDef)
2. The different statuses
There are a number of standard statuses that can be returned by the printer driver.
<-- Enumerated type -->
Public Enum Printer_Status
PRINTER_STATUS_READY = &H0
PRINTER_STATUS_PAUSED = &H1
PRINTER_STATUS_ERROR = &H2
PRINTER_STATUS_PENDING_DELETION = &H4
PRINTER_STATUS_PAPER_JAM = &H8
PRINTER_STATUS_PAPER_OUT = &H10
PRINTER_STATUS_MANUAL_FEED = &H20
PRINTER_STATUS_PAPER_PROBLEM = &H40
PRINTER_STATUS_OFFLINE = &H80
PRINTER_STATUS_IO_ACTIVE = &H100
PRINTER_STATUS_BUSY = &H200
PRINTER_STATUS_PRINTING = &H400
PRINTER_STATUS_OUTPUT_BIN_FULL = &H800
PRINTER_STATUS_NOT_AVAILABLE = &H1000
PRINTER_STATUS_WAITING = &H2000
PRINTER_STATUS_PROCESSING = &H4000
PRINTER_STATUS_INITIALIZING = &H8000
PRINTER_STATUS_WARMING_UP = &H10000
PRINTER_STATUS_TONER_LOW = &H20000
PRINTER_STATUS_NO_TONER = &H40000
PRINTER_STATUS_PAGE_PUNT = &H80000
PRINTER_STATUS_USER_INTERVENTION = &H100000
PRINTER_STATUS_OUT_OF_MEMORY = &H200000
PRINTER_STATUS_DOOR_OPEN = &H400000
PRINTER_STATUS_SERVER_UNKNOWN = &H800000
PRINTER_STATUS_POWER_SAVE = &H1000000
End Enum
3. The data structures
As each printer driver is responsible for returning this data there has to be a standard to which this returned data conforms in order for one application to be able to query a number of different types of printers. As it happens, there are nine different standard data types that can be returned by the GetPrinter API call in Windows 2000 (only the first two are universal to all current versions of Windows).
Of these, the second is the most interesting - named PRINTER_INFO_2 <-- Data structure -->
Private Type PRINTER_INFO_2
pServerName As String
pPrinterName As String
pShareName As String
pPortName As String
pDriverName As String
pComment As String
pLocation As String
pDevMode As Long
pSepFile As String
pPrintProcessor As String
pDatatype As String
pParameters As String
pSecurityDescriptor As Long
Attributes As Long
Priority As Long
DefaultPriority As Long
StartTime As Long
UntilTime As Long
Status As Long
JobsCount As Long
AveragePPM As Long
End Type
However, it is not as simple as just passing this structure to the GetPrinter API call as a printer can return more information than is in that structure and if you do not allocate sufficent buffer space for it to do so your application will crash.
Fortunately the API call caters for this - if you pass zero in the pbSize parameter then the API call will tell you how big a buffer you will require in the pbSizeNeeded.
This means that filling the information from the printer driver becomes a two step process:
<-- Using the GetPrinter API call -->
Dim lret As Long
Dim SizeNeeded As Long
Dim buffer() As Long
ReDim Preserve buffer(0 To 1) As Long
lret = GetPrinterApi(mhPrinter, Index, buffer(0), UBound(buffer), SizeNeeded)
ReDim Preserve buffer(0 To (SizeNeeded / 4) + 3) As Long
lret = GetPrinterApi(mhPrinter, Index, buffer(0), UBound(buffer) * 4, SizeNeeded)
<-- Retrieving the string part -->
However the buffer is just an array of Long data types. Some of the data within the PRINTER_INFO_2 data structure is String data. This must be collected from the addresses which are stored in the appropriate buffer position.
To get a string from a pointer the CopyMemory API call is used and there is also an API call, IsBadStringPtr, which can be used to verify that the address pointed to does actually contain a valid string.
<-- Declarations -->
'\\ Memory manipulation routines '
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Destination As Any, Source As Any, ByVal Length As Long)
'\\ Pointer validation in StringFromPointer
Private Declare Function IsBadStringPtrByLong Lib "kernel32" Alias "IsBadStringPtrA" (ByVal lpsz As Long, ByVal ucchMax As Long) As Long
Retrieving the string from a pointer is a common thing to have to do so it is worth having this utility function in your arsenal.
Public Function StringFromPointer(lpString As Long, lMaxLength As Long) As String
Dim sRet As String
Dim lret As Long
If lpString = 0 Then
StringFromPointer = ""
Exit Function
End If
If IsBadStringPtrByLong(lpString, lMaxLength) Then
'\\ An error has occured - do not attempt to use this pointer
StringFromPointer = ""
Exit Function
End If
'\\ Pre-initialise the return string...
sRet = Space$(lMaxLength)
CopyMemory ByVal sRet, ByVal lpString, ByVal Len(sRet)
If Err.LastDllError = 0 Then
If InStr(sRet, Chr$(0)) > 0 Then
sRet = Left$(sRet, InStr(sRet, Chr$(0)) - 1)
End If
End If
StringFromPointer = sRet
End Function
So to use this to populate your PRINTER_INFO_2 variable:
With mPRINTER_INFO_2 '\\ This variable is of type PRINTER_INFO_2
.pServerName = StringFromPointer(buffer(0), 1024)
.pPrinterName = StringFromPointer(buffer(1), 1024)
.pShareName = StringFromPointer(buffer(2), 1024)
.pPortName = StringFromPointer(buffer(3), 1024)
.pDriverName = StringFromPointer(buffer(4), 1024)
.pComment = StringFromPointer(buffer(5), 1024)
.pLocation = StringFromPointer(buffer(6), 1024)
.pDevMode = buffer(7)
.pSepFile = StringFromPointer(buffer(8), 1024)
.pPrintProcessor = StringFromPointer(buffer(9), 1024)
.pDatatype = StringFromPointer(buffer(10), 1024)
.pParameters = StringFromPointer(buffer(11), 1024)
.pSecurityDescriptor = buffer(12)
.Attributes = buffer(13)
.Priority = buffer(14)
.DefaultPriority = buffer(15)
.StartTime = buffer(16)
.UntilTime = buffer(17)
.Status = buffer(18)
.JobsCount = buffer(19)
.AveragePPM = buffer(20)
End With
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