The first IDE tape drive. Subsequent drives are numbered ht1 etc. They are character devices on major node 37 and start at minor node 0 for ht0 1 for ht1 etc. The first analogue joystick. The dev-name should be set before registering the input device by the input device driver. It's a string like 'Generic button device' containing a user friendly name of the device. The id. fields contain the bus ID (PCI, USB.), vendor ID and device ID of the device. The bus IDs are defined in input.h. This uses the OS device /dev/input/js0 by default. In theory, any joystick device that the OS mounts like this can be used. In practice, the behavior will change depending on the model of joystick ( Sony, or knockoff ), or XBox controller and the Bluetooth driver used to support it.
Index
Overview
This program listen in the background for gamepad inputs. If a special button combination is getting pressed,the provided command line will be invoked. It runs a command once defined buttons were pressed. It was developed for Raspbian and PS3 wireless controller but should work everywhere with udev and joystick support.
Usage
I have a Raspberry Pi. The installed operation system is raspbian. The Kodi package runs pretty well as a media center. The remote control is an App on a smartphone. So no other controller is needed.
After couple of month I found this great RetroPie project. There is also another great one which brings it on a software level instead making a boot image. It's called EmulationStation. The setup with my preferred PS3 controller and the configuration went well and it worked fantastic. The game console works perfectly fine and brings me back to the good old jump'n'run 90s but now with big screen and cool wireless controller!
But one thing was an issue. I wanted to use the same hardware and don't miss my system (raspbian). Dual boot is not cool and takes too long. So basically what i needed is some kind of trigger to end any X11/Kodi processes and start EmulationStation .. and of course vice versa.
In my configuration Kodi runs as default. Media center is still the primary usage. But the idea was to take the PS3 controller press some button combination and the EmulationStation will apear. After I played enough, just press this buttons again and media center will apear and I can put the PS3 controller back.
After searching the internet, I found nothing really interesting. Kodi addon will not work because gamepad support is still missing. EmulationStation addon might work but than .. Kodi solution will be missing. So I had to go one level up to the OS. But even here I found nothing really easy to setup or working. So I decided to write this program. It runs as a daemon in the background and listening in nonblocking mode to /dev/input/js* devices. To make it hotplug capable, it's monitoring the udev signals if no device is present.
Update 12/22/2018:If you have many different /dev/inputs, you can pass it as an arguement at the startup:
jslisten --device /dev/input/js0
** jslisten will also default to listen to the first device found if the defined device is not found.
Update 02/12/2019:Changed the default service user to 'pi' in jslisten.service
Use user root only if it's really required.
Update 02/16/2019:Added a different mode to easier trigger scripts.
When started with
--mode plain Ample guitar vst mac download. (the default) the program behaves as used. This is fine if you need the button combination once in a while.
However if you want to activate a script a few times in a short time, lets say to adjust your audio volume or if you have a led stripe installed in your arcade and want to adjust the brightness, thenthe
--mode hold comes in handy.
When started with
--mode hold and you have at least two buttons defined to enter an action, then you hold down the first one, while tipping the second one. If you have three buttons defined you canhold the second two and then just tip the third. In a four button set you will have to hold the first three.
As soon as you release any but the last button (according to the order in the
jslisten.cfg ) you will have to press the all buttons again.
So the difference to the plain mode is that once you have entered the engaged/elevated state with a three button set for example, you hold down the first two and can quickly trigger the action bypressing the third. In plain mode you would have to press all three buttons over again to do audio or brightness adjustment.
Also added
--help for the command line for a brief summary of options.
Installation
Following example for Raspbian. Should work for many other distributions almost the same way.
Configuration
Here is my config example:
Known limitations
Multiple key combinations
You can have different key sets to run different programs:
When you open a file, all kinds of things can go wrong. A file lives on a physical device — a fixed disk, for example, or perhaps on a flash drive or SD card — and you can run into problems when working with physical devices.
For example, part of the disk might be damaged, causing an existing file to become corrupted. Or, less disastrous, you might run out of disk space. Or, even less disastrous, you might try to open a file in a directory that doesn’t exist.
If you try to open a file for writing by specifying a full path and filename but the directory does not exist, the computer responds differently, depending on the operating system you’re using. If you’re unsure how your particular operating system will respond, try writing a simple test application that tries to create and open something like /abc/def/ghi/jkl/abc.txt. (Of course, you’ll want to be sure to use a directory that doesn’t exist.)
Then one of two things will happen: Either the directory and the file will get created, or nothing will happen.
For example, on a Windows system, if we attempt to create a file in a directory that doesn’t exist, the system does not create the directory. That’s because deep down inside, the application ultimately calls an operating system function that does the dirty work of creating the file. And this particular operating system function (it’s called CreateFile(), if you even care) has a rule that it will not create a directory for you.
If you want to determine whether the ostream class was unable to create a file, you can call its fail() member function. This function returns true if the object couldn’t create the file. And that’s what happens when a directory doesn’t exist. The DirectoryCheck01 example shown demonstrates an example of this.
When you run this code, assuming that you don’t have a directory called /abc/def/ghi on your system, you should see the message Couldn’t open the file! Assuming that your particular operating system doesn’t create a directory in this case; if it does, your computer will open the file, write Hi to it, and move on with its happy life after closing things out.
As an alternative to calling the fail() member function, you can use an operator available in various stream classes. This is !, fondly referred to as the “bang” operator, and you would use it in place of calling fail(), as in this code:
Most people prefer to use !outfile instead of outfile.fail(), although !outfile makes confusing code. The reason is that outfile is an object, and the notion of !outfile simply doesn’t make sense.
Create Device File Dev Input Js0 C 1
In fact, !outfile trips up many beginning programmers. They know that outfile is not a pointer in this sample code, and they wonder how you could test it against 0 as you normally can only do with a pointer. (Remember, by saying !x, where x is some pointer, you’re testing x against 0.) And that simply doesn’t make sense! And so, to avoid confusion, just call fail(). It makes more sense.
Here are some reasons your file creation may choke:
Create Device File Dev Input Js0 C 9
Like any good application, your application should do two things:
Create Device File Dev Input Js0 C 0
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