Re: Opening a new window,and cd to the same directory as the currentwindow,no matter what I'm doing

[samuel.lethiec]

Eventually, I've found a way to do this. I thought some of you might be

interested, so... 







I'm quoting myself here:

> 3) How is the current window number stored in screen? I mean, is there a

command, a register or something,

> that would tell me the current window number? Then I could store it in a

variable before creating the new

> window...

> 

> and... since on every window, the variable $WINDOW is defined (at window

creation, I know, but I don't 

> change the window number), in my ~/.bashrc, I could find back the process

with $WINDOW = current window,

> and then find its CWD





Few answers latter I was already dreaming:

> 

> I'd need something like the 'exec' command but which would take the

environment from the shell of the

> current window, not the parent shell

> 



But actually, combine these two ideas, and you've got something not so

crasy! ;)



let me explain why:



==

exec [[fdpat] newcommand [args ...]]

Run a unix subprocess (...)in the current window

==



The WINDOW environment variable is also defined for the subprocess!

(As I already said, I never move window araund, so $WINDOW is always the

current windown umber, but it 

might not always be the case for you...)



All we have to do now is to find back the current window process pid, and

then read its /proc/${pid}/cwd



Since this process and the subprocess have the same PPID, this makes things

even easier :)



Here is the 'interesting' part of my screen-utils.bash:





=====

#!/bin/bash

# Author: samlt

# This script is intended to be run within a screen session



# Find the PWD of the window process, from which this script is called

function getSameDir () { #{{{

   local WINNB pid 

   # find the current window process pid

   while read pid; do

      [[ $$ == $pid ]] && continue

      WINNB=$(tr '\000' '\n' </proc/${pid}/environ | sed -n

'/^WINDOW=/s///p')

      [[ -z "${WINNB}" ]] && continue

      [[ ${WINDOW} -eq ${WINNB} ]] && break

   done < <(ps --ppid ${PPID} --noheader -o %p | sed 's/^[[:space:]]*//')



   # check if we really found something, or if we've just reached the end

of the loop

   [[ ${WINDOW} -eq ${WINNB} ]] || exit 2

   echo $(readlink /proc/${pid}/cwd)

}

#}}}



# Open(in the background?) a new window in the same dir as the (local)

process on the current window

function newWindow () { # {{{

   local DIR="$(getSameDir)"

   # screen -X eval screen "stuff 'cd \"$DIR\"^M^L'" other

   screen -X eval screen "stuff 'cd \"$DIR\"^M^L'"

}

# }}}



# (sniiiip...)



###############

# "main"

########

      

# if WINDOW is not set, no need to go further, we're not in a screen

session

[[  -z ${WINDOW} ]] && exit 1

case "${1}" in

   nw)

      newWindow

      ;;

   # (sniiiip...)

esac



# vim: set et sts=3 sw=3 foldmethod=marker :

====





Now to open a new window (and cd to the same directory as the current

window) while you're working on

a remote box, or simply if you don't have your (local) prompt available

just issue



:exec /path/to/screen-utils.baeh nw



:)



Now make a shortcut, and enjoy :)