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I am creating an instance configuration script that sets up a machine.

I am running the script via sudo i.e. sudo run.sh. Most of the steps require root access but some of the script's steps do no require root access and I prefer running them as the unprivileged user who ran the sudo.

Inside the script running with sudo, I am trying to do

sudo -i -u username sh -c 'echo $MY_ENV'

Since .bashrc contains export MY_ENV=something I expect the above command to print "something"

How can I temporarily switch inside the script to the other user to run commands that include the user's shell env ?

Michael
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  • possible duplicate of su options - running command as another user – jasonwryan Apr 11 '15 at 07:46
  • @jasonwryan I've seen that but it says nothing about including the user's env vars as well – Michael Apr 11 '15 at 07:48
  • @Michael: Take a look at su's option -. – Cyrus Apr 11 '15 at 08:24
  • Try removing "sh -c" arguments. – Andy Apr 11 '15 at 10:25
  • @jasonwryan - This isn't about sudo or su, I think. Michael - when you call sh you don't get bashrc doing anything - even if sh is a link to bash. You can do ENV=~/.bashrc sh -c 'cmd' though, maybe. A possible issue with that though is sudo. You can do sudo env - ENV=~/.bashrc sh -c 'cmd. Though I'm not positive if it will correctly work with -c - have to check that. Oh. jasonwryan - maybe it is about sudo after rereading the question. I guess we're talking about .bashrc influencing the command before it is run, not a shell's init file. – mikeserv Apr 11 '15 at 10:51
  • @Cyrus tried any combination of that, couldn't get it to work, still would not print what's in the .bashrc file – Michael Apr 11 '15 at 19:17
  • Try this: su USERNAME -c "bash -i -c 'echo foo'" – Cyrus Apr 11 '15 at 19:24

1 Answers1

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.bashrc is executed only by interactive shells, not by scripts¹. It's the wrong place to define environment variables. See Is there a ".bashrc" equivalent file read by all shells? and the Ubuntu wiki.

You can tell bash to read .bashrc explicitly. Of course you'll have to execute bash, not sh which could be a different shell:

sudo -i -u username bash -c '. `~/.bashrc; echo "$MY_ENV"'

But it's a bad idea because .bashrc files are likely to contain things that assume that they're executed on a terminal and that spend time setting up key bindings, aliases, prompts, etc.

The sane solution is to put environment variable definitions where they belong, in ~/.profile or ~/.pam_environment.

¹ Except when bash is called by sshd for some weird reason.

Community
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Gilles 'SO- stop being evil'
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