I need to detect a keypress in a console application, without prompting the user. Basically, my app is normally a daemon that listens to a special input device, but i need to simulate it on a dev box using the keyboard in interactive mode. How can I do this? - Im on a Linux system.
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u know -- linux, keyboard input, curses – Cheers and hth. - Alf Sep 03 '12 at 09:27
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possible duplicate of [Capturing Keystrokes in GNU/Linux in C](http://stackoverflow.com/questions/1485116/capturing-keystrokes-in-gnu-linux-in-c) – Christian.K Sep 04 '12 at 05:18
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If you can't block while waiting for input, then you can use e.g. select to check if the STDIN_FILENO file descriptor is ready for reading, and if it is then you can use normal input functions (scanf, fgets std::getline, etc.).
Some programmer dude
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Does this actually work? In my testing (using the example from the select man page), select doesn't report that stdin is ready for reading until it sees a CR. – Joe Strout Jul 21 '17 at 14:15
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@JoeStrout You probably have to update the terminal flags as well, using [`tcsetattr`](http://pubs.opengroup.org/onlinepubs/009695399/functions/tcsetattr.html). – Some programmer dude Jul 21 '17 at 19:08
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Yes, that appears to be the case on my test machines at least (one OS X, one Ubuntu). – Joe Strout Jul 22 '17 at 20:40
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You check this answer which explains how to read from the input events ( usually /dev/input/event0)
Or directly check the answer's source :
Credits do not go to me, this code is taken from the Ventriloctrl hack to get keystrokes. http://public.callutheran.edu/~abarker/ventriloctrl-0.4.tar.gz
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This text explaines hw to do such a thing. http://thc.org/papers/writing-linux-kernel-keylogger.txt
Software_Designer
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