在bash中分叉子外壳时如何加载环境变量？

Question

The next bash script was called in crontab.

I defined some environment variables for python in /etc/profile.d/python.sh.

$JOBCMD was some python script which will runing for long time, so I want to the script be called with fork.

#!/bin/sh

. /etc/profile.d/python.sh

JOBCMD=`/path/to/a_long_time_shell.py`

if [ -z "$variable" ]; then
    (
        . /etc/profile.d/python.sh
        $JOBCMD &
    )
fi

exit 0

The result is $JOBCMD can't get environment variables in /etc/profile.d/python.sh? How can I do to fix it?

Answer 1

The easiest way I can see of doing this is to export the variables in python.sh :

export a=123
export b=234

instead of

a=123
b=234

which I guess you're doing.

Or if you know which variables you want, you could export them before you call the script:

...
. /etc/profile.d/python.sh
export a
export b
$JOBCMD &
...

Answer 2

export JOBCMD=`/path/to/a_long_time_shell.py`

Should make it available to all newly created process. Or, even better. You could use psutils to find the process by name and do something with it that way. Passing things into the environment is a weird way to do IPC.