I am writing Junit test cases using SWTBot.
One such test case is on Keyboard.
I have written a test case using pressKeyBoardShortCut(keystroke) and i am passing keystrokes, but it is dependent on my physical keyboard of my system.
I dont want my test case to depend on physical keyboard. Is there way i can use automated keyboard in SWTBot or any other way to avoid physical keyboard so that when ever a keyboard test case is run it run fine even though the keyboard is not connected to system.
Please let me know, waiting for the replies.
SWTBot supports a few keyboards layouts to map character to keycode. If a keyboard layout is not supported, it will fail back to English so it may note produce the expected behaviour (because it won't create the right keyboard events).
You should consider contributing the keyboard layout that is missing so it would work as expected for you https://wiki.eclipse.org/SWTBot/Keyboard_Layouts#Creating_keyboard_layouts .
Related
I am dealing with an issue in Ubuntu. I want to get current keyboard cursor position in terminal via Gcc
any assist...
"Terminal" is a program, or more accurately a description of a large class of programs, which implements a graphical interface emulating an external terminal (which would have been connected to your computer via a serial cable, or in some similar fashion). Your program communicates with the terminal emulator through a kind of bidirectional pipe (a "pseudoterminal") implemented by the operating system; to your program it looks like a pair of ordinary streams (stdin and stdout).
Linux itself has a terminal emulator, called "the console", which can be used instead of a window manager. Few programmers use it these days, but it's still there if you want to experiment. The console is a "terminal" (and there are usually several of them which you can switch between using a control+function key). As you might expect from the words "terminal" and "pseudoterminal", these basically look the same to your application.
There are a ton of details, which I'm skipping over because it would take a book to describe the whole thing.
The only connection between your program and the terminal (or pseudoterminal) is that you can send it a stream of characters, and you can receive a stream of characters from it. There is no other communication. There's no hidden operating system interface, because the terminal emulator is not part of the operating system. It's not even part of the window manager. It's just another userland application running without special privileges, just like your application.
You often want to do things other than just send characters to the output device. Maybe you want to clear the screen, or move the cursor to another location, or change the colour of the text or the background. All of these things are done by sending specially coded sequences interspersed with the text you're displaying. The operating system doesn't mediate or verify these sequences, and there's no definitive standard for how the terminal emulator should interpret them, but there is common framework which most terminal emulators conform to, to some extent, which makes it possible to actually write code which doesn't need to know exactly which terminal emulator is being used at the moment. The terminfo library is commonly used to describe the available terminals; by convention, the environment variable TERM contains the name of the relevant terminfo configuration, and that configuration can be used to create concrete control sequence strings suitable for the configured terminal [Note 1].
Now let's get back to your initial question: "how do I find out the current cursor location?" That's one of a small number of possible queries, which are also implemented as control sequences. Specifically, you send the terminal a control sequnce which asks it where the cursor is (usually the four characters \x1B[6n) and the terminal eventually replies with a control sequence which might look something like \x1B12,7R meaning that the cursor was on row 12 at column 7 at the moment that the control sequence was sent [Note 2]. So you could use terminfo to help you send the query and then attempt to parse the reply when it comes.
Note that the response is not synchronous with the query, since the user could be typing while the query is sent. (However, the response is sent as a contiguous sequence.) So part of the parsing process is disentangling the user input from the query response.
My guess is that you don't actually want to do all that work. In most cases, if you want to write a console application which does something less boring than just write output sequentially to a terminal window, you should use ncurses (also maintained by Thomas Dickey) or some other similar library. Ncurses takes full responsibility for maintaining the console image, jumping through the necessary hoops to communicate with the terminal emulator; one of its features is to keep track of the current cursor position [Note 3].
Another option, if you are only trying to provide better line editing and tab completion, is to use the GNU Readline library, or similar interfaces available for other operating systems.
Notes
This might or might not be the terminal you're actually using, since TERM is just an environment variable. You could set it yourself if you wanted it.
I took those codes from man 4 console_codes; another good source of information is Thomas Dickey's terse list of code sequences understood by xterm.
As far as I know, Ncurses does not use the cursor-position query to figure out where the cursor is on the screen. It maintains its own copy of the screen being displayed, which includes the current cursor position. You can use the macro getyx() to ask for what it considers the current cursor position.
I have an RFID tag reader. But it works like a HID device (like a keyboard). It sends keystrokes to the computer when a tag is scanned. When I open notepad and scan a tag - it types the ID one digit at a time. Is there a way to create a program to listen to this device (or this port) and capture (intercept) all input. So that the keystrokes wouldn't appear on my system but I could assign my own events when the device sends and input. I don't want it to show up on Notepad.
I realize that the implementation can differ depending on the OS and programming language used. Ideally, I would like to make this work on both Windows and Linux. I would prefer to use something like Node.js but I suppose C could also be good.
I would appreciate any hints or pointing me in the right direction.
You could open the raw input device for reading (basically ioctl with parameter EVIOCGRAB for Linux and RegisterRawInputDevices() for Windows as discussed here and here). However, the mechanisms are quite different for Windows and Linux, so you will end up implementing all the low-level logic twice.
It should also be possible to read the input data stream from the standard input just like you would read an input from the keyboard (e.g. scanf() or fgets() in C) with some logic that recognizes when a data set (= tag ID) is complete - the reader device might for example terminate an input with a newline '\n' or null character '\0'.
You should probably do this in a separate thread and have some kind of producer-consumer mechanism or event model for communication with your main application.
I'm trying to make a simple game for the unix terminal, written in c. I've
been looking for a way to poll the keyboard, but haven't had any luck.
Currently I'm using ncurses getch() function. It works okay but if the user holds a key, the keyboard repeat will take a moment to start - also it will halt if any other key is pressed. This causes problems when playing (especially in two player mode where both games are controlled from a single input thread).
For example, if player 1 holds down 'a' and player 2 holds down 'b', I need to poll the keyboard and handle a stream of input like this:
abababababababab
As another example, if player 1 holds down the 'a' key and also presses the 'b' key, I need the input to be handled like this:
aaaaaaabaaaaaaaa
This way the simultaneous key presses don't interrupt each other. So I basically need to poll the keys on the keyboard on a set interval, and create my own implementation of a key press repeater.
Is there a way in c (with or without ncurses) to simply poll the keyboard on a time interval and read in all keys that are currently being pressed? From there I can just design the keyboard input thread to manage repeating actions manually. Basically something along the lines of kbhit, so I can check the status of a given key. But that will also let me poll the arrow keys.
It doesn't work that way:
Basically something along the lines of kbhit, so I can check the status of a given key. But that will also let me poll the arrow keys.
In any system that doesn't allow direct access to the hardware (MS-DOS is the only example you're likely to have encountered, others would include embedded systems), you're only able to read a sequence of characters (not keys) in a terminal application. GUI applications rely upon a server which does access some of the hardware (more) directly, but transforms the data.
In a terminal (such as used by ncurses), you can only check if the incoming characters includes the one that corresponds to the keyboard-key that you're interested in. Arrow keys send a sequence of characters: with ncurses you can either read the individual characters in the sequence, or rely upon ncurses to match the sequence to a known key in the terminal description.
Even with system-specific things such as the Linux console, you won't find much support for reading the keyboard as a whole: only character events. Read kbd_mode and console_ioctl to see what's available, keeping in mind this ancient caveat from the latter:
Warning: Do not regard this man page as documentation of the Linux
console ioctls. This is provided for the curious only, as an
alternative to reading the source. Ioctl's are undocumented Linux
internals, liable to be changed without warning. (And indeed, this
page more or less describes the situation as of kernel version
1.1.94; there are many minor and not-so-minor differences with
earlier versions.)
The suggested link Receiving key press and key release events in Linux terminal applications? gives some useful information. But as noted, the question (aside from the last point mentioned) is a duplicate.
I want to make a snake game without using graphics. The problem is that the snake will have to change direction when pressing the corresponding button. How do I make my program respond to my button without needing to scan a character. Because, if I add an instruction such as scanf() or getch(), my snake would stop moving and that's not how a snake game works.
The implementation is dependent on the system you want to use. Windows has other functions to check for keypresses than Linux. For Windows you can use Console.KeyAvailable. For Linux you can best look at a console library like ncurses.
On every system it is possible to have getchar()(or similar functions) non-blocking. On Unix system, the solution is to set the terminal (tty) in raw mode. To simplify your life, you can also use some library to do it for you, a lib like curses or one of its variants. Such a lib will also help you to draw chars on screen exactly as you may dream for an ASCII snake program.
There is also different solutions on Windows system.
You can also use multi-threading. One thread blocking on terminal I/Os and transmitting read chars to the other moving the snake.
Hello I am new to C programming but I am making a menu for a game. I have a fish in ascii art displayed and it gets moved one character over every .5 secs. I accomplish this by a simple loop and it keeps on going across the screen then when it reaches the end, the fish is cleared and then it gets repeated again. Now while this animation is going on I would like to prompt the user for an input, however when I do that with getchar or scanf for example the fish loop waits until I press something and the animation stops until I press a key. Coould someone please shed some light on my problem??
Thank-you
You can't do this with any of the standard input methods. You're going to either have to use something like ncurses, or put the terminal into raw mode and do some pretty fancy manipulations. I have no idea what platform you're on, but raw mode is difficult under Linux, and even harder under Windows, so I'd stick with a library if you can.
Welcome to the world of Threads.
To understand threads think of how your computer works. If your computer ran without threads, you would not be able to run multiple applications at the same time. Threads allow for multiple parts of a program or interface to run at the same time without depending on eachother.
In your case, you will want a thread for the input and a separate thread for the animation. Thus allowing both to run separately.