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According to the screen manual (version 4.0.2.)

C-a x
C-a C-x     (lockscreen)  Lock this terminal.
C-a X       (remove)      Kill the current region.

But what actually happens when I use it (Screen version 4.00.03 (FAU) 23-Oct-06):

C-a X   locks the terminal and asks me for the password. When I enter the correct passwword, I am back in screen but the region is killed (wtf)
C-a x   does nothing apparently

Please note the differences between x (lowercase) and X (uppercase).

Why is there a mixup between the functionalities of C-a X and C-a x? How can I fix this?

I am on CentOS release 5 (Final).

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migrated from Oct 8 '11 at 8:38

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I don't know about the case mixup.

But I'm assuming that the 'Kill the current region' does nothing because you only use one region.

Start another region using C-aS (horizontal split) or C-a| (vertical split, only on recent versions of screen).

Now you can use C-aX to kill a region, or C-aQ to keep only the currently active region (similar to C-aC-d and re-attach with screen -DR -- resetting the region layout)

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"> But I'm assuming that the 'Kill the current region' does nothing because you only use one region." But I did create a new region before doing Ctrl-a X! – gojira Oct 7 '11 at 9:35
@gojira: sry, no need to be shouting. You didn't say it, and it is not uncommon for users of screen to confuse windows and regions – sehe Oct 7 '11 at 9:37
I am not shouting, I just clarified that I already had a region open which I thought was implied, but probably I was not clear enough. So yes, the region is open it's just that the functionalities of C-a X and C-a x are mixed up. Would be happy if someone knows the reason or a solution. Thanks. – gojira Oct 12 '11 at 7:05

Perhaps your screenrc (personal or system wide) has changed these bindings from the defaults.

To see what they're currently set to, view the bindings by hitting the "help" combo -- C-a?.

See if the entries for lockscreen and remove match what the man page says.

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