How do I detect arrow keys pressed using curses in C?

Question

In trying to get input from the arrow keys via curses (ncurses) it won't catch as KEY_UP etc. I used the keypad function with a true argument but getch still returned an escaped sequence. How do I shift through the values returned by getch() and grab the arrow keys specifically?

As of 2023, [here](https://stackoverflow.com/a/75499310/6013016) is the solution — Scott, Feb 20 '23 at 00:06

score 23 · Answer 1 · edited Nov 09 '11 at 18:07

23

I found the same problem on Mac OS X. But it was resolved by adding the following:

keypad(stdscr, TRUE);

edited Nov 09 '11 at 18:07

Jason Plank

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answered Oct 18 '09 at 22:09

Paul Franz

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This and storing `getch` as `int` worked for me. – bpisano Sep 23 '21 at 08:49
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This doesn't answer the question – Thomas Dickey Feb 19 '23 at 14:50

score 19 · Accepted Answer · edited Jan 03 '14 at 15:17

19

I was storing getch() calls as char's when they were supposed to be int's. Works perfectly after the switch.

edited Jan 03 '14 at 15:17

Chris Seymour

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answered Jul 25 '09 at 19:16

Actually, this should have been closed because the question did not show the program that would have demonstrated the problem. – Thomas Dickey Feb 19 '23 at 14:55

score 9 · Answer 3 · answered Jul 25 '09 at 18:25

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Standard (VT100-like) terminals send a sequence of characters when the arrow keys are pressed. You just have to keep track of whether or not these are pressed in sequence. Here are the char's to watch for:

Down Arrow  0x1B 0x5B 0x42
Left Arrow  0x1B 0x5B 0x44
Right Arrow 0x1B 0x5B 0x43
Up Arrow    0x1B 0x5B 0x41

answered Jul 25 '09 at 18:25

Ryan Ballantyne

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Are there escape codes you could enter as a key combination or sequence using ctrl for these? – Sean A.O. Harney Jul 25 '09 at 19:11
No need; you can type them directly. 0x1B = esc, 0x5B = [, and 0x41 - 0x44 = A - D. Type esc[D in your terminal, and the cursor moves to the left. – Ryan Ballantyne Jul 25 '09 at 19:27
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This approach pretty much fully defeats the whole purpose of working with curses library in the first place :-) – Andrew Y Jul 26 '09 at 08:41
This doesn't answer the question – Thomas Dickey Feb 19 '23 at 14:51

How do I detect arrow keys pressed using curses in C?

3 Answers3

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