OSError: [Errno 22] Invalid argument while copy capabilities from InputDevice to UInput

[chrys87]

Howdy, I currently write a screenreader deamon for linux. for this i need to "consume" the shortcuts for the screenreader because there should no other programm react to it. so i need to grab the InputDevices -> Check ist the keypress for me? No -> write it back to the "normal" input line for other programms. so i try to generate a UInput class per InputDevice and i like to have the same capabilities (because later i just forewart the input) If i define the UInput variable with (see example):

uDevices[fd] = UInput( dev.capabilities())

i get the following error: Traceback (most recent call last): File "<stdin>", line 7, in <module> File "/usr/lib/python3.5/site-packages/evdev/uinput.py", line 104, in __init__ _uinput.enable(self.fd, etype, code) OSError: [Errno 22] Invalid argument

if i try something more simple it works: from evdev import UInput, AbsInfo, ecodes as e t = UInput({ e.EV_KEY : [e.KEY_A, e.KEY_B]})

so somehow it seems that it is not able to parse.

Did i something wrong? can I got this working somehow? is this maybe a bug?

the following example code gives me the error:

import evdev
from evdev import InputDevice, UInput
from select import select
import time

iDevices = map(evdev.InputDevice, (evdev.list_devices()))
iDevices = {dev.fd: dev for dev in iDevices if dev.fn in ['/dev/input/event14']} # event14 is in my example a keyboard
uDevices = {}
for fd in iDevices:
    dev = iDevices[fd]
    print(dev.capabilities(verbose=True))
    print('-----------')
    print(dev.capabilities(verbose=False))    
    print('-----------')    
    uDevices[fd] = UInput( dev.capabilities())

the prints give me the following:

{('EV_MSC', 4): [('MSC_SCAN', 4)], ('EV_SYN', 0): [('SYN_REPORT', 0), ('SYN_CONFIG', 1), ('?', 4), ('?', 17), ('?', 20)], ('EV_KEY', 1): [('KEY_ESC', 1), ('KEY_1', 2), ('KEY_2', 3), ('KEY_3', 4), ('KEY_4', 5), ('KEY_5', 6), ('KEY_6', 7), ('KEY_7', 8), ('KEY_8', 9), ('KEY_9', 10), ('KEY_0', 11), ('KEY_MINUS', 12), ('KEY_EQUAL', 13), ('KEY_BACKSPACE', 14), ('KEY_TAB', 15), ('KEY_Q', 16), ('KEY_W', 17), ('KEY_E', 18), ('KEY_R', 19), ('KEY_T', 20), ('KEY_Y', 21), ('KEY_U', 22), ('KEY_I', 23), ('KEY_O', 24), ('KEY_P', 25), ('KEY_LEFTBRACE', 26), ('KEY_RIGHTBRACE', 27), ('KEY_ENTER', 28), ('KEY_LEFTCTRL', 29), ('KEY_A', 30), ('KEY_S', 31), ('KEY_D', 32), ('KEY_F', 33), ('KEY_G', 34), ('KEY_H', 35), ('KEY_J', 36), ('KEY_K', 37), ('KEY_L', 38), ('KEY_SEMICOLON', 39), ('KEY_APOSTROPHE', 40), ('KEY_GRAVE', 41), ('KEY_LEFTSHIFT', 42), ('KEY_BACKSLASH', 43), ('KEY_Z', 44), ('KEY_X', 45), ('KEY_C', 46), ('KEY_V', 47), ('KEY_B', 48), ('KEY_N', 49), ('KEY_M', 50), ('KEY_COMMA', 51), ('KEY_DOT', 52), ('KEY_SLASH', 53), ('KEY_RIGHTSHIFT', 54), ('KEY_KPASTERISK', 55), ('KEY_LEFTALT', 56), ('KEY_SPACE', 57), ('KEY_CAPSLOCK', 58), ('KEY_F1', 59), ('KEY_F2', 60), ('KEY_F3', 61), ('KEY_F4', 62), ('KEY_F5', 63), ('KEY_F6', 64), ('KEY_F7', 65), ('KEY_F8', 66), ('KEY_F9', 67), ('KEY_F10', 68), ('KEY_NUMLOCK', 69), ('KEY_SCROLLLOCK', 70), ('KEY_KP7', 71), ('KEY_KP8', 72), ('KEY_KP9', 73), ('KEY_KPMINUS', 74), ('KEY_KP4', 75), ('KEY_KP5', 76), ('KEY_KP6', 77), ('KEY_KPPLUS', 78), ('KEY_KP1', 79), ('KEY_KP2', 80), ('KEY_KP3', 81), ('KEY_KP0', 82), ('KEY_KPDOT', 83), ('KEY_ZENKAKUHANKAKU', 85), ('KEY_102ND', 86), ('KEY_F11', 87), ('KEY_F12', 88), ('KEY_RO', 89), ('KEY_KATAKANA', 90), ('KEY_HIRAGANA', 91), ('KEY_HENKAN', 92), ('KEY_KATAKANAHIRAGANA', 93), ('KEY_MUHENKAN', 94), ('KEY_KPJPCOMMA', 95), ('KEY_KPENTER', 96), ('KEY_RIGHTCTRL', 97), ('KEY_KPSLASH', 98), ('KEY_SYSRQ', 99), ('KEY_RIGHTALT', 100), ('KEY_HOME', 102), ('KEY_UP', 103), ('KEY_PAGEUP', 104), ('KEY_LEFT', 105), ('KEY_RIGHT', 106), ('KEY_END', 107), ('KEY_DOWN', 108), ('KEY_PAGEDOWN', 109), ('KEY_INSERT', 110), ('KEY_DELETE', 111), (['KEY_MIN_INTERESTING', 'KEY_MUTE'], 113), ('KEY_VOLUMEDOWN', 114), ('KEY_VOLUMEUP', 115), ('KEY_POWER', 116), ('KEY_KPEQUAL', 117), ('KEY_PAUSE', 119), ('KEY_KPCOMMA', 121), (['KEY_HANGEUL', 'KEY_HANGUEL'], 122), ('KEY_HANJA', 123), ('KEY_YEN', 124), ('KEY_LEFTMETA', 125), ('KEY_RIGHTMETA', 126), ('KEY_COMPOSE', 127), ('KEY_STOP', 128), ('KEY_AGAIN', 129), ('KEY_PROPS', 130), ('KEY_UNDO', 131), ('KEY_FRONT', 132), ('KEY_COPY', 133), ('KEY_OPEN', 134), ('KEY_PASTE', 135), ('KEY_FIND', 136), ('KEY_CUT', 137), ('KEY_HELP', 138), ('KEY_F13', 183), ('KEY_F14', 184), ('KEY_F15', 185), ('KEY_F16', 186), ('KEY_F17', 187), ('KEY_F18', 188), ('KEY_F19', 189), ('KEY_F20', 190), ('KEY_F21', 191), ('KEY_F22', 192), ('KEY_F23', 193), ('KEY_F24', 194), ('KEY_UNKNOWN', 240)], ('EV_LED', 17): [('LED_NUML', 0), ('LED_CAPSL', 1), ('LED_SCROLLL', 2), ('LED_COMPOSE', 3), ('LED_KANA', 4)]}
-----------
{0: [0, 1, 4, 17, 20], 1: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 113, 114, 115, 116, 117, 119, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 240], 4: [4], 17: [0, 1, 2, 3, 4]}
-----------

[gvalkov]

Hello @chrys87,

It's just poorly documented :( Filtering out the EV_SYN capabilities is enough to get it working:

cap = dev.capabilities()
del cap[0]
ui = UInput(capabilities)

I think I'll add an UInput.from_device() class method to make this more straightforward.

Please let me know if you run into any more trouble. Good luck with your project!

[chrys87]

Hi gvalkov,

Thanks for you fast help. Indeet this works as except :+1: Yea maybe it should documented anywhere XD. and UInput.from_device() method would been awsome!

[chrys87]

the new command works like a charm :) thanks!!