2

Not sure what I'm doing wrong here.

User2 sources a file in it's .bash_profile to set environment specific aliases.

# .bash_profile
source $HOME/set_environment_shortcuts

Inside $HOME/set_environment_shortcuts (there are many aliases in here). Example:

alias startservices="verylongcommand"

Now I would like to 'startservices from another user. 

[User1@server1 ~]$ sudo su -l User2 -c '. ~/.bash_profile; startservices'
-bash: startservices: command not found

The runuser command produces the same result.

[User1@Server1 ~]$ sudo runuser -l User2 -c '. ~/.bash_profile; startservices'
-bash: startservices: command not found

Do aliases not work in this way?

Note, when bypassing the alias entirely, the command works.

Kusalananda
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Motorahead
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  • Is startservices defined in the other user's ~/.bash_profile? – Satō Katsura Sep 25 '17 at 20:03
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    You realize that ~ means home directory (as does $HOME), and that different users have different home directories, right?  Please [edit] your question to be a whole lot clearer about what is defined in whose file, and which user is executing which command. – Scott - Слава Україні Sep 26 '17 at 01:02

2 Answers2

5

Aliases are not expanded when the shell is not interactive, unless the expand_aliases shell option is set with shopt -s expand_aliases.

Aliases are a shortcut tool for use interactively. For any kind of scripting, use a shell function instead:

startservices () {
    # commands go here
}

Shell functions are a lot more flexible than aliases in many ways. They are able to take arguments like a shell script does, for starters:

startservices () {
    user="$1"
    service="$2"
    # code to start service "$service" as user "$user"
}

You should not have to source the other user's .bash_profile explicitly. Use sudo -i instead. This will start a login shell, which will read .bash_profile when starting:

$ sudo -i -u User2 startservices

This requires startservices to either be a script or other external utility in the $PATH of User2, a shell function defined in the shell startup files of User2, or an alias (with the shell running with expand_aliases set) defined in the shell startup files of User2.

See also Is there ever a good reason to run sudo su?

Kusalananda
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  • I see, thanks. I'll need to rebuild the script that sets the alias, to instead set functions. I will test using functions shortly. As for "sudo -i". It creates a different problem. I tried it earlier and the command prompts User1 for a password even though the user is a sudoer. – Motorahead Sep 25 '17 at 21:43
  • So I ended up using expand_aliases. It seems to be a cleaner approach than rebuilding the entire script. The script sets aliases based on three factors, user/host/environment. Within the alias there are variables that pick up strings based on those factors as well. Assigning the aliases to a function that applies to many user environments made most sense with my knowledge of scripting.

    Is shopt -s expand_aliases considered acceptable use, and not really a band-aid approach? What are the pros/cons to this?

     – Motorahead Sep 25 '17 at 23:17
  • @Motorahead I would honestly do a function for this, it sounds like a lot of logic and parameters could be built into the function, which would make it self-contained. I'm guessing you now have a lot of logic tests that sets of some variation of the alias based on the environment. This logic could be moved into the function. – Kusalananda Sep 26 '17 at 08:37
  • Yeah there a bunch of logic tests that determine which function to call, thus setting the aliases. I'll have to look at containing that logic into a function as you mentioned. Thanks! – Motorahead Sep 26 '17 at 21:27
0

The alias is defined in user1's .bash_profile . When you use "su -l user2" it actually clears all the environment variables for user1 and loads user2's variables instead, where no "startservices' alias is defined.

You can use "su -p " option which will preserve the current environment, but in that case user2 has to have read permission on user1's .bashrc file.

Reaz Mahmood
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