Where to create an environmental variable ?

[Denna]

If you want to create an environmental variable with the "export" command, what script should it run from ?

 

[RMerlin]

profile.add.

 

[RMerlin]

Source the profile file at the start of your postconf script. profile.add only adds env vars when a user logs in over ssh, it can't be retroactively applied to already running processes such as rc.

 

[thelonelycoder]

Does the script have to be profile.add or can it be any executable script ?

For example, /jffs/scripts/env-vars.sh contains ...

export IPSET="/usr/sbin/ipset"

/jffs/scripts dnsmasq.postconf contains ...

#!/bin/sh

. /jffs/scripts/env_vars.sh
$IPSET options

When you source a file in a proper script, it does not matter where or what form the file is in as long as what is written in it is understood and valid.
No shebang, no executable rights needed for that file.
Test it!

 

[Denna]

Scenario #1:

a) When sourcing ". /jffs/configs/profile.add" in /jffs/scripts/dnsmasq.postconf, the environment variable is set.
​

Scenario #2:

a) The profile.add file was copied to /jffs/scripts and renamed to env_vars.sh.
b) The commands in /jffs/configs/profile.add were commented out.
c) When sourcing ". /jffs/scripts/env_vars.sh" in /jffs/scripts/dnsmasq.postconf, the environment variable is not set.​

 

[thelonelycoder]

Scenario #1:

a) When sourcing ". /jffs/configs/profile.add" in /jffs/scripts/dnsmasq.postconf, the environment variable is set.
​

Scenario #2:

a) The profile.add file was copied to /jffs/scripts and renamed to env_vars.sh.
b) The commands in /jffs/configs/profile.add were commented out.
c) When sourcing ". /jffs/scripts/env_vars.sh" in /jffs/scripts/dnsmasq.postconf, the environment variable is not set.​

No reason not to.
Why don't you try and figure out why by yourself?

 

[Denna]

@RMerlin,

Is this correct ? At bootup ...

• /etc/profile is processed before dnsmasq.postconf
• The profile.add script runs after dnsmasq.postconf
• Since /etc/profile is read-only, by sourcing profile.add in dnsmasq.postconf, the variables are made available to all shells that would normally only be present after a user logs into the OS.
  
• For any sourced script in dnsmasq.postconf that creates variables, those variables will not be available to dnsmasq.postconf when the sourced script exits