CHECKPNGFORMAT Printer Escape function

The CHECKPNGFORMAT printer escape function determines whether a printer supports printing a PNG image.

To perform this check, call the ExtEscape function with the following parameters.

Syntax

int ExtEscape(
  _In_  HDC    hdc,
  _In_  int    nEscape,
  _In_  int    cbInput,
  _In_  LPCSTR lpszInData,
  _In_  int    cbOutput,
  _Out_ LPSTR  lpszOutData
);

Parameters

• hdc [in]
  A handle to the printer device context.

• nEscape [in]
  The escape function to be performed.

  Value	Meaning
  CHECKPNGFORMAT	Checks whether the printer supports printing a PNG image.

   

• cbInput [in]
  The size, in bytes, of the PNG image buffer pointed to by the lpszInData parameter.

• lpszInData [in]
  A pointer to a buffer that contains the PNG image.

• cbOutput [in]
  The number of bytes of data pointed to by the lpszOutData parameter.

  For this escape, set this value to sizeof ( DWORD ).

• lpszOutData [out]
  A pointer to the DWORD variable that receives the output from this escape. This parameter must not be NULL.

  If the printer supports the image type, this value is set to 1. Otherwise, it is set to zero.

Return value

The return value is greater than zero if the function is successful and less than zero if not. A return value of zero indicates that the printer does not support this check.

Remarks

Before using the CHECKJPEGFORMAT printer escape function, call the QUERYESCSUPPORT printer escape function to determine whether the driver supports CHECKJPEGFORMAT. For sample code, see Testing a Printer for JPEG or PNG Support.

Requirements

See also

Printing

GDI Printer Escape Functions

ExtEscape

QUERYESCSUPPORT

CHECKJPEGFORMAT