ultravnc
When pressing the keys Ctrl, Shift and etc on the server side is constantly pressed and released.
I use a certain program in RHEL 7 and RHEL 8 under wine and noticed such a feature that when holding down the ctrl key in RHEL 8 sometimes it is not processed (for example, open a new tab (Ctrl + mouse click)).
Did a little research and found that the issue occurs starting with tigervnc-server 1.9.0, possibly due to "Alternative, "raw" keyboard mode in the native client and all servers" (https://github.com/TigerVNC/tigervnc/releases).
Regardless, I also found a workaround to solve my problem, but I'm afraid it will break something else. The workaround is to enable the Japanese keyboard in the UltraVNC client. With the Japanese keyboard enabled, I don’t see my problem, but in "xev" I see a single press, and not a lot of "press release".
I would like to understand if the problem is related to UltraVNC, TigerVNC or the application I am using?
Here is the XEV log without the Japanese keyboard:
KeyPress event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499643, (883,496), root:(933,611),
state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XmbLookupString gives 0 bytes:
XFilterEvent returns: False
KeyRelease event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499670, (883,496), root:(933,611),
state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XFilterEvent returns: False
KeyPress event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499670, (883,496), root:(933,611),
state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XmbLookupString gives 0 bytes:
XFilterEvent returns: False
KeyRelease event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499701, (883,496), root:(933,611),
state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XFilterEvent returns: False
KeyPress event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499701, (883,496), root:(933,611),
state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XmbLookupString gives 0 bytes:
XFilterEvent returns: False
KeyRelease event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499736, (883,496), root:(933,611),
state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XFilterEvent returns: False
KeyPress event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499736, (883,496), root:(933,611),
state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XmbLookupString gives 0 bytes:
XFilterEvent returns: False
KeyRelease event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499761, (883,496), root:(933,611),
state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XFilterEvent returns: False
KeyPress event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499761, (883,496), root:(933,611),
state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XmbLookupString gives 0 bytes:
XFilterEvent returns: False
KeyRelease event, serial 28, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196499774, (883,496), root:(933,611),
state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XFilterEvent returns: False
and with Japanese keyboard:
KeyPress event, serial 30, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196551230, (200,4), root:(250,119),
state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XmbLookupString gives 0 bytes:
XFilterEvent returns: False
KeyRelease event, serial 30, synthetic NO, window 0x1a00001,
root 0x31c, subw 0x0, time 2196557882, (200,4), root:(250,119),
state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
XLookupString gives 0 bytes:
XFilterEvent returns: False
I also noticed that if the client is running in debug mode and the Japanese keyboard is enabled, the log is interrupted by the following message:
rdr::Exception (1): rdr::SystemException: read: Unknown error (10004)
Here is the full log:
Started and Winsock (v 2) initialised
bufsize expanded to 4352
Registered connection with app
Saving to C:\Users\USER\AppData\Roaming\UltraVNC\options.vnc
DPI 96
Reset keyboard for first use
Flush dead key gives: 1 character(s): 0x0020 ( )
Connected to SERVER port 5905
DSMPlugin not enabled
RFB server supports protocol version 3.8
Connected to RFB server, using protocol version 3.8
VNC authentication succeeded
Read a 43-byte string
Desktop name "SERVER:5 (USER) "
Geometry 1536 x 801 depth 24
Screen work area is 1680 x 1010
Reset keyboard for first use
Flush dead key gives: 1 character(s): 0x0020 ( )
Clipboard changed
Ignore Clipboard while initializing!
No next window in chain; WM_DRAWCLIPBOARD will not be passed
SetClipboardViewer to 0x0017091a; next is 0x0001023c. Last error 0x00000000Screen work area is 1680 x 1010
Update-processing thread started
Screen work area is 1680 x 1010
Screen work area is 1680 x 1010
Receiving cursor shape update, cursor 0x0
Receiving cursor shape update, cursor 8x20
bufsize expanded to 8448
Receiving cursor shape update, cursor 15x21
Receiving cursor shape update, cursor 15x21
rdr::Exception (1): rdr::SystemException: read: Unknown error (10004)
Update-processing thread finishing
WndProchwnd ChangeClipboardChain hwnd 0x0017091a / m_hwndcn 0x0017091a, 0x00000000 (1)
Deregistered connection from app
Exiting
VNC viewer closing down
