Can one set an environment variable globally

ConnorBehan · 2007-10-15 20:59:11

I am running a script in v/c 2 that looks like this:

#!/bin/bash 
TURNEDON=1
until [ 6 -eq 9 ]; do
  if [ $TURNEDON -eq 0 ]; then
    poweroff
  else
    sleep 5
  fi
done

The idea is, it checks to see if TURNEDON has become 0 every 5 seconds and if so, turns off the computer. I would like to be able to shutdown by setting TURNEDON=0 in v/c 1.

The problem is, whenever I run TURNEDON=0, set TURNEDON=0, env TURNEDON=0 or export TURNEDON=0, this script will still see it as a 1 because I have not set TURNEDON=0 globally. Is there any command or series of steps to change the value of TURNEDON to 0 such that every process (or at least this script) will inherit it?

Last edited by ConnorBehan (2007-11-09 18:35:42)

kumico · 2007-10-15 23:24:48

/etc/profile

Gilneas · 2007-10-15 23:31:09

kumico wrote:

/etc/profile

No, I don't believe that would do... He wants to change the environment of a running process.

I too have been wondering if this is possible. (The only thing I found out was printing the environment of a running process 'ps auxwwe | grep processname')

nj · 2007-10-15 23:35:46

I'm not sure if you can set an env variable globally, but you can use a file instead.

#!/bin/bash 
until [ 6 -eq 9 ]; do
  TURNEDON=`cat ~/.poweroff`
  if [ "$TURNEDON" = "0" ]; then
    echo 1 > ~/.poweroff
    poweroff
  else
    sleep 5
  fi
done

Then 'echo 0 > ~/.poweroff' to poweroff.

ConnorBehan · 2007-10-15 23:39:33

Oh I see... so instead of checking if TURNEDON=0 (in which case it check's its own environment) I'd use 'ps auxwwe | grep processname' to check if I have set TURNEDON=0 in some other process's environment. I think for my purposes it would be much easier to work with files for this. The script now looks like this.

#!/bin/bash 
rm /home/dummy
until [ 6 -eq 9 ]; do
  if [ -e /home/dummy ]; then
    poweroff
  else
    sleep 5
  fi
done

And to shutdown I simply run touch /home/dummy. After using this method several times I may have some claim as to why I like it better than a normal shutdown lol.

ConnorBehan · 2007-11-09 18:37:18

I am again in a situation where I'm trying to find how to change a process' environment. In this case it is xfce4-panel because I want to change the anchor points of the panel when I change workspaces. There is a GUI to do this quickly, but the code that happens when you click the button, isn't a shell command, it's a series of C functions and GTK API calls that I don't know how to script... so I'm trying to trick xfce4-panel into thinking I clicked the button by changing variables.

iphitus · 2007-11-09 22:27:21

you cannot change an environmental variable "globally" in all running processes at once.

colinzhengj · 2007-11-10 08:46:30

ConnorBehan wrote:

I am again in a situation where I'm trying to find how to change a process' environment. In this case it is xfce4-panel because I want to change the anchor points of the panel when I change workspaces. There is a GUI to do this quickly, but the code that happens when you click the button, isn't a shell command, it's a series of C functions and GTK API calls that I don't know how to script... so I'm trying to trick xfce4-panel into thinking I clicked the button by changing variables.

There is no clean way to do so. Best bet is to patch source code of xfce4-panel

Arch Linux

#1 2007-10-15 20:59:11

Can one set an environment variable globally

#2 2007-10-15 23:24:48

Re: Can one set an environment variable globally

#3 2007-10-15 23:31:09

Re: Can one set an environment variable globally

#4 2007-10-15 23:35:46

Re: Can one set an environment variable globally

#5 2007-10-15 23:39:33

Re: Can one set an environment variable globally

#6 2007-11-09 18:37:18

Re: Can one set an environment variable globally

#7 2007-11-09 22:27:21

Re: Can one set an environment variable globally

#8 2007-11-10 08:46:30

Re: Can one set an environment variable globally

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