On Mon, 19 Oct 2015 20:47:34 +0200 Axel Beckert <a...@deuxchevaux.org> wrote:
> Hi, > > On Sun, Oct 18, 2015 at 11:13:07PM +0000, Anonymous wrote: > > A shell script needs to be able to add a window, and know in advance > > what window number is still available. It will then do some > > stuffing. > > > > ATM it's quite messy and complex. The script attempts to randomly > > create a title then use that as a handle, but then it must > > eventually rename the window to something sensible. Sometimes it > > screws up and clobbers an existing window. > > Which screen commandline parameters do you use for that? I'd expect > something like "screen -X screen 63 somecommand". (Would run > "somecommand" in a window with number 63 unless that number is already > in use.) > > > I need a more sensible option. E.g. I need to be able to do > > something like "screen -x user/session -windowlist", and simply get > > a dump of windows, which the script can then parse. > > Have you tried "screen -Q windows"? Unfortunately it seems to be > truncated to the width of the screen session's bottom line. Luckily it > seems truncated at the beginning, i.e. you always see the highest > number: > > Get the highest window number: > > $ screen -Q windows | sed -e > 's/^.*[^0-9]\([0-9][0-9]*\)[^0-9]*\$[^$]*$/\1/' 10 > $ > > Run "mc" in a window with one window number higher than the highest > one (i.e. always a predetermined window number): > > $ screen -X screen $(($(screen -Q windows | sed -e > 's/^.*[^0-9]\([0-9][0-9]*\)[^0-9]*\$[^$]*$/\1/')+1)) mc > > (needs bash or zsh for $((expression)) to work) > > Or separated to reuse the window number elsewhere: > > $ windownumber=$(($(screen -Q windows | sed -e > 's/^.*[^0-9]\([0-9][0-9]*\)[^0-9]*\$[^$]*$/\1/')+1)) $ echo Window > will be created with number $windownumber $ screen -X screen > $windownumber mc > > HTH. > > Kind regards, Axel Hey, Just to add, on new versions (from 4.3.0) it is also possible to do something like: screen -Q windows "%n %t\n" to list window titles, it should return window numbers and titles on separate lines Like: $ screen -S test -Q windows "%n %t\n" 0 zsh 1 zsh 2 zsh You can use it to determine first free "missing number" for example in $ screen -S test -Q windows "%n %t\n" 0 zsh 2 zsh next window will be 1 or use in combination with 'collapse' command (also introduced in 4.3.0) and then use wc -l to get window number $ ./screen -Q windows "%n %t\n" 0 zsh 2 zsh $ ./screen -X collapse $ ./screen -Q windows "%n %t\n" 0 zsh 1 zsh $ ./screen -Q windows "%n\n" | wc -l 2 $ windownumber=$(./screen -Q windows "%n\n" | wc -l) $ echo $windownumber Best Regards, Amadeusz _______________________________________________ screen-users mailing list screen-users@gnu.org https://lists.gnu.org/mailman/listinfo/screen-users
