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I use GNU Screen's scrollback/copy mode. So I hit Control-A [ to enter copy mode, scroll up to the section I care about... and then I forget.

However, it seems like leaving GNU screen in scrollback/copy mode blocks execution of (whatever app was up at the time). For example, if I fire up a local webserver if I'm in scrollback/copy mode, then requests made to that web server will time out: the process doesn't respond until I exit copy/scrollback mode.

I've seen this both in Ruby On Rails script/server and with the Python tool Paste.

I've considered turning on logging mode for my windows, then just tailing/grepping through those logfiles as an alternative, but if this can be controlled by another means (setting, activating copy mode a different way) I'm very interested.

My screen -version says:

Screen version 4.00.03 (FAU) 23-Oct-06

(I asked this on, but maybe this is a better place)

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The reason that your processes are blocking is because screen will block the output pipe of the process while you are in copy paste mode. I don't see it as really being a bug, since realistically you are asking screen to store a potentially unlimited amount of information in its buffer while you are copy/pasting. If you want to have output of a program pass by, but also be able to pause it once in a while, try this.

program > logfile 2>&1 & 
less logfile

The 2>&1 will combine stderr and stdout from your program. The & sends the program into the background. Use fg to bring it to the foreground if you need. Now press F to follow the end of the logfile as it grows with less. Press ctrl+c if you need to stop and examine something, then F to follow again. You can also press & to limit the visible lines in less to a regular expression. Very handy when going through log files.

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