FAQ 8.6 How do I check whether input is ready on the keyboard?

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8.6: How do I check whether input is ready on the keyboard?

The easiest way to do this is to read a key in nonblocking mode with the
Term::ReadKey module from CPAN, passing it an argument of -1 to indicate
not to block:

use Term::ReadKey;

ReadMode('cbreak');

if (defined ($char = ReadKey(-1)) ) {
# input was waiting and it was $char
} else {
# no input was waiting
}

ReadMode('normal'); # restore normal tty settings



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