c++ - Programmatically ascertain whether TWAIN scanner is turned on -


i using twain in c++ program control epson scanner, , have things working intended, 1 exception:

when scanner not turned on, , scan command sent error window epson scan: "cannot communicate scanner. make sure scanner turned on (etc)".

rather rely on check scanner turned on on launch of program. there way (using twain or not - perhaps scan of connected, powered-on usb devices?) of achieving this?

i'm afraid not achivable twain. however, can check epson , see if provide related api detect / control error window in twain driver, can better manage error display.

here similar discussion can check out.


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