unix上有现成的函数可用，Windows上我也不知道，Windows做了太多的工作然后并且不公开文当。
另外，有些答应机关机了也能处理打印作业(就是不出纸)。
试试这个吧：PRINTER_INFO_2.status
Status
Specifies the printer status. This member can be any reasonable combination of the following values. Value Meaning
PRINTER_STATUS_BUSY The printer is busy.
PRINTER_STATUS_DOOR_OPEN The printer door is open.
PRINTER_STATUS_ERROR The printer is in an error state.
PRINTER_STATUS_INITIALIZING The printer is initializing.
PRINTER_STATUS_IO_ACTIVE The printer is in an active input/output state
PRINTER_STATUS_MANUAL_FEED The printer is in a manual feed state.
PRINTER_STATUS_NO_TONER The printer is out of toner.
PRINTER_STATUS_NOT_AVAILABLE The printer is not available for printing.
PRINTER_STATUS_OFFLINE The printer is offline.
PRINTER_STATUS_OUT_OF_MEMORY The printer has run out of memory.
PRINTER_STATUS_OUTPUT_BIN_FULL The printer\'s output bin is full.
PRINTER_STATUS_PAGE_PUNT The printer cannot print the current page.
Windows 95/98/Me: Indicates the page is being \"punted\" (that is, not printed) because it is too complex for the printer to print.
PRINTER_STATUS_PAPER_JAM Paper is jammed in the printer
PRINTER_STATUS_PAPER_OUT The printer is out of paper.
PRINTER_STATUS_PAPER_PROBLEM The printer has a paper problem.
PRINTER_STATUS_PAUSED The printer is paused.
PRINTER_STATUS_PENDING_DELETION The printer is being deleted.
PRINTER_STATUS_POWER_SAVE The printer is in power save mode.
PRINTER_STATUS_PRINTING The printer is printing.
PRINTER_STATUS_PROCESSING The printer is processing a print job.
PRINTER_STATUS_SERVER_UNKNOWN The printer status is unknown.
PRINTER_STATUS_TONER_LOW The printer is low on toner.
PRINTER_STATUS_USER_INTERVENTION The printer has an error that requires the user to do something.
PRINTER_STATUS_WAITING The printer is waiting.
PRINTER_STATUS_WARMING_UP The printer is warming up.
