typically one would not pin-point or otherwise tell the user exactly what is wrong with the input. either restrict the character set in the input (i.e. per keystroke) or just tell them it's not valid and what the valid characters are. unless that's the whole point of the application.
the hardest line to type correctly is: stty erase ^H

In reply to Re: getting stripped characters from string by aquarium
in thread getting stripped characters from string by Anonymous Monk

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