Имею практически аналогичную проблему. Пускаю тот же xev с выводом в файл и тыкаю мультимедийную клавишу, получается вот такой набор текста с кодом, который начинающему пользователю будет 100 % абсолютно не понятен:
Outer window is 0x5800001, inner window is 0x5800002
PropertyNotify event, serial 8, synthetic NO, window 0x5800001,
atom 0x27 (WM_NAME), time 70388638, state PropertyNewValue
PropertyNotify event, serial 9, synthetic NO, window 0x5800001,
atom 0x22 (WM_COMMAND), time 70388638, state PropertyNewValue
PropertyNotify event, serial 10, synthetic NO, window 0x5800001,
atom 0x28 (WM_NORMAL_HINTS), time 70388638, state PropertyNewValue
CreateNotify event, serial 11, synthetic NO, window 0x5800001,
parent 0x5800001, window 0x5800002, (10,10), width 50, height 50
border_width 4, override NO
PropertyNotify event, serial 14, synthetic NO, window 0x5800001,
atom 0x10d (WM_PROTOCOLS), time 70388638, state PropertyNewValue
MapNotify event, serial 15, synthetic NO, window 0x5800001,
event 0x5800001, window 0x5800002, override NO
PropertyNotify event, serial 18, synthetic NO, window 0x5800001,
atom 0x11b (_NET_WM_STATE), time 70388639, state PropertyNewValue
PropertyNotify event, serial 18, synthetic NO, window 0x5800001,
atom 0x115 (_NET_WM_DESKTOP), time 70388639, state PropertyNewValue
ConfigureNotify event, serial 18, synthetic NO, window 0x5800001,
event 0x5800001, window 0x5800001, (0,0), width 178, height 178,
border_width 0, above 0x28002ad, override NO
ReparentNotify event, serial 18, synthetic NO, window 0x5800001,
event 0x5800001, window 0x5800001, parent 0x140a8f8,
(6,19), override NO
ConfigureNotify event, serial 18, synthetic NO, window 0x5800001,
event 0x5800001, window 0x5800001, (6,19), width 178, height 178,
border_width 0, above 0x140a907, override NO
ConfigureNotify event, serial 18, synthetic YES, window 0x5800001,
event 0x5800001, window 0x5800001, (423,293), width 178, height 178,
border_width 0, above 0x140a8f8, override NO
MapNotify event, serial 18, synthetic NO, window 0x5800001,
event 0x5800001, window 0x5800001, override NO
VisibilityNotify event, serial 18, synthetic NO, window 0x5800001,
state VisibilityUnobscured
Expose event, serial 18, synthetic NO, window 0x5800001,
(0,0), width 178, height 10, count 3
Expose event, serial 18, synthetic NO, window 0x5800001,
(0,10), width 10, height 58, count 2
Expose event, serial 18, synthetic NO, window 0x5800001,
(68,10), width 110, height 58, count 1
Expose event, serial 18, synthetic NO, window 0x5800001,
(0,68), width 178, height 110, count 0
PropertyNotify event, serial 18, synthetic NO, window 0x5800001,
atom 0x137 (WM_STATE), time 70388643, state PropertyNewValue
PropertyNotify event, serial 18, synthetic NO, window 0x5800001,
atom 0x1a7 (_NET_WM_ALLOWED_ACTIONS), time 70388643, state PropertyNewValue
PropertyNotify event, serial 18, synthetic NO, window 0x5800001,
atom 0x11b (_NET_WM_STATE), time 70388643, state PropertyNewValue
FocusIn event, serial 18, synthetic NO, window 0x5800001,
mode NotifyNormal, detail NotifyNonlinear
KeymapNotify event, serial 18, synthetic NO, window 0x0,
keys: 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
PropertyNotify event, serial 18, synthetic NO, window 0x5800001,
atom 0x112 (_NET_FRAME_EXTENTS), time 70388643, state PropertyNewValue
PropertyNotify event, serial 18, synthetic NO, window 0x5800001,
atom 0x11b (_NET_WM_STATE), time 70388643, state PropertyNewValue
PropertyNotify event, serial 28, synthetic NO, window 0x5800001,
atom 0x1a9 (_NET_WM_ICON_GEOMETRY), time 70388660, state PropertyNewValue
KeyRelease event, serial 29, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70388688, (102,-29), root:(525,264),
state 0x0, keycode 104 (keysym 0xff8d, KP_Enter), same_screen YES,
XLookupString gives 1 bytes: (0d) "
"
XFilterEvent returns: False
FocusOut event, serial 32, synthetic NO, window 0x5800001,
mode NotifyGrab, detail NotifyAncestor
FocusIn event, serial 32, synthetic NO, window 0x5800001,
mode NotifyUngrab, detail NotifyAncestor
KeymapNotify event, serial 32, synthetic NO, window 0x0,
keys: 18 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
KeyPress event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70390684, (102,-29), root:(525,264),
state 0x0, keycode 10 (keysym 0x31, 1), same_screen YES,
XLookupString gives 1 bytes: (31) "1"
XmbLookupString gives 1 bytes: (31) "1"
XFilterEvent returns: False
KeyRelease event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70390689, (102,-29), root:(525,264),
state 0x0, keycode 10 (keysym 0x31, 1), same_screen YES,
XLookupString gives 1 bytes: (31) "1"
XFilterEvent returns: False
KeyPress event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70390692, (102,-29), root:(525,264),
state 0x0, keycode 36 (keysym 0xff0d, Return), same_screen YES,
XLookupString gives 1 bytes: (0d) "
"
XmbLookupString gives 1 bytes: (0d) "
"
XFilterEvent returns: False
VisibilityNotify event, serial 32, synthetic NO, window 0x5800001,
state VisibilityPartiallyObscured
FocusOut event, serial 32, synthetic NO, window 0x5800001,
mode NotifyNormal, detail NotifyNonlinear
EnterNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70392360, (123,6), root:(546,299),
mode NotifyNormal, detail NotifyNonlinear, same_screen YES,
focus NO, state 0
KeymapNotify event, serial 32, synthetic NO, window 0x0,
keys: 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70392360, (123,6), root:(546,299),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70392368, (125,12), root:(548,305),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70392376, (129,21), root:(552,314),
state 0x0, is_hint 0, same_screen YES
LeaveNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70392384, (134,31), root:(557,324),
mode NotifyNormal, detail NotifyNonlinear, same_screen YES,
focus NO, state 0
VisibilityNotify event, serial 32, synthetic NO, window 0x5800001,
state VisibilityUnobscured
Expose event, serial 32, synthetic NO, window 0x5800001,
(0,25), width 10, height 43, count 2
Expose event, serial 32, synthetic NO, window 0x5800001,
(68,25), width 110, height 43, count 1
Expose event, serial 32, synthetic NO, window 0x5800001,
(0,68), width 178, height 110, count 0
EnterNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393920, (176,11), root:(599,304),
mode NotifyNormal, detail NotifyNonlinear, same_screen YES,
focus NO, state 0
KeymapNotify event, serial 32, synthetic NO, window 0x0,
keys: 68 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393920, (176,11), root:(599,304),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393928, (176,10), root:(599,303),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393936, (175,8), root:(598,301),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393944, (175,6), root:(598,299),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393952, (174,5), root:(597,298),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393960, (174,4), root:(597,297),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393968, (174,3), root:(597,296),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393976, (174,2), root:(597,295),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393984, (174,1), root:(597,294),
state 0x0, is_hint 0, same_screen YES
MotionNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70393992, (174,0), root:(597,293),
state 0x0, is_hint 0, same_screen YES
LeaveNotify event, serial 32, synthetic NO, window 0x5800001,
root 0x1ad, subw 0x0, time 70394000, (174,-2), root:(597,291),
mode NotifyNormal, detail NotifyNonlinear, same_screen YES,
focus NO, state 0
FocusIn event, serial 32, synthetic NO, window 0x5800001,
mode NotifyNormal, detail NotifyNonlinear
KeymapNotify event, serial 32, synthetic NO, window 0x0,
keys: 68 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
ClientMessage event, serial 32, synthetic YES, window 0x5800001,
message_type 0x10d (WM_PROTOCOLS), format 32, message 0x10b (WM_DELETE_WINDOW)
И после этого вы ещё говорите, что всё просто? 