Getting $USER inside shell script when running with sudo?

unix shell environment-variables sudo
Jörg Haubrichs picture Jörg Haubrichs · Oct 27, 2009 · Viewed 20.3k times · Source

How do I get the correct $USER if I run a shell script with sudo ?

I run them as postinstall scripts in a Mac install package, where they are being sudo-ed automatically, but I need to do stuff with the username.

$HOME is correct, though. The inelegant method would be to extract the name from the home path, but I wonder if there is a natural way to do this.

I can't influence the way the scripts are being called, as it's an automatic call inside the installer.

Answer

dz. picture dz. · Oct 27, 2009

On my system the variable $SUDO_USER is set to the caller's user name.

You shouldn't extract the username from the ${HOME} variable directly. It's being configured and not calculated. To Extract the username you could take a look into /etc/passwd file, but this is very system dependent, e.g. sometimes you have to look into a LDAP directory or the entries are propagated through NIS ...

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